@ConcernedUser X20 isn't going to do much for you.

WiFi 7 is supposed to have lower latency.

  @McFly Hmm, would neither the X20, X50 or X60 provide a bit of a better signal between Decos to reduce latency?

If I could wire the Decos together I don't think I'd need anything other than the M5's, right? They can handle the speed I get.

I don't know if any of my devices even support WiFi 7, so a WiFi 7 TP-Link Deco seems out of the question, not to mention the cost. 

  @ConcernedUser WiFi 6 has lower latency, not as low as 7 though.

Sure, unless you have clients with 6 or 7 it won't make much difference.

X90 is tri-band, more antennas, more streams so it may help.

X60 is faster than X50/X20 but I don't know if it will do much for you.

Yes, wired M5s would probably be good enough.

  @ConcernedUser 

I started the Deco journey with a combination of E4R and M5.

At the time this combination was fine, and in fact relatively trouble free. But at the time I had all Wi-Fi 5 products and did not stream more than one High Definition stream. 

But as time progressed, I changed my laptop to a MacBook with Wi-Fi 6 and now have many Wi-Fi 6 and other new IOT products, a home server that holds 4K films, my entire photo library, all my music and is also used for local backups for three laptops. Plus now I work from home and often use Teams, Google Meet etc, all wirelessly.

In the main, the M5 and E4R setup managed well, but it strained a little when I moved to a bigger house with highly insulated walls. I also wanted to equip the 1 acre grounds with cameras, and due to the lack of power, I needed to extend my system outdoors. 

I bought an X50-Outdoor which does a reasonable job of connecting the various solar powered cameras over wi-fi. But punching through the foil insulation was nigh on impossible. I resorted to a set of Powerline Adapters, but they caused no end of issues with the backhaul, disconnecting regularly (contacted TP-Link here but they ran out f ideas and went silent on me).

It was at that point I decided it was time to update to wi-fi 6. The new outdoor Deco is wi-fi 6 so it seemed sensible to match the same. Apparently there is a limit of 6 Deco nodes on wi-fi 5 (unknown to me at the time as TP-Link blurb said it was theoretically unlimited). As soon as I pointed this "unlimited" to TP-Link, they removed the blurb.

So I bought three X55 understanding wi-fi 6's ability to punch through walls and insulation is superior to that of wi-fi 5.

On installing, the signal quality was........the same. Not impressed. However, the speed of the network was considerably better inside the house. But the coverage of "up to 6500 sq/ft was inadequate toc cover my 2500 sq/ft house. So if I am to suggest anything, its to ignore the coverage figures which appear to be grossly inflated. Three X55 should more than cover my house, but sadly no.

SO I bought two X60 to bolster the network, using one for upstairs and the remaining 4 downstairs between the Conservatory at one end to the Living Room at the other. The second of the two X60 connects to the outdoor Deco being as close as it can be to it. Still the signal flicks between Weak and Medium. Most of the internal Decos report a Medium Connection even though the distance between them is no further than around 8 metres.

But by far the biggest issue is Customer Support which appears to be selective. If you ask a question on here you can flip a coin as to whether you get an answer or not. Follow up is the same, 50/50. Personally I have never had a 100% resolution to any of my problems on here. The support agents seem to get so far then either lose interest, forget about you, or just haven't got a clue what the problem is and chose silence rather than admitting defeat publicly. That said, most issues are down to Firmware issues. And this is not limited to Deco, I sent back 9 KASA radiator TRVs to Amazon because they released Firmware that broke the TRVs (and two of my radiator valves) and then went on a fortnight's holiday leaving me with no alternative than to remove them all and refit the dumb valves. I now use a Tado (not Tapo) system and it works very well. TP-Link seem to release poorly tested Firmware, most of which can be read about on here. Its a sign of the times that the public seem to be unpaid Beta testers now, relying on unhappy customers' feedback rather than testing a release a lot more before launching it.

Conclusion: Your M5 system is functional and basic. Relatively speaking its proven technology and I never had any issues with mine. By moving to the latest technology, my warning would not be about the product, but about the support you will get if it all goes wrong. If the speed you are experiencing is adequate, then why change? And yes, you will lose free Homecare to the newer subscription based service which is great for TP-Link, but not the customer. I refuse to subscribe to such services, but then I have all Macs in my house so the security side of things is sorted with a good firewall, which I have in my chosen modem.

If you decide to change; Hope for the best, expect the worse.

  @McFly Thanks. I did look at the X90 for that reason, but it's marked as end of life on the Deco site. Worried about the long term support there. 

For me it's not the speed so much as the coverage and latency between wireless Decos I'm hoping to improve.

  @SteveWex Thank you very much for taking the time to reply and share your experience, glad to read your post.

For me, you're right the M5 is functional and basic. But I've had them for about 3 years now, and I'm worried the performance has degraded because they're constantly running hot. Not just warm, but uncomfortably hot. 

TP-Link offered to replace them, albeit with refurbished models which I thought was fair. But given I feel the M5 have a bit of a design flaw, they offered to let me pay the difference to get another refurb model, such as the X50/X60 and I'm not sure it's worth missing the opportunity if possible, right? 

____________________________________________________________________________________________

Not so glad to hear about the problems you had going from the E4R/M5 to the much more expensive models.

I appreciate the fair warning that the coverage is likely going to be the same. I've read a lot of conflicting reports on that. It seems strange to me that the newer models, despite being more expensive, don't provide better coverage even if it's listed on the box. I suppoes I experienced similar where my S4's seem to give better coverage than my M5. I just thought after this many years there would be even a slight difference.

It's more disappointing to hear about the signal strength. That was one of my main factors for considering the upgrade. I can't believe they'd be weak when placed that close. The weird thing on my network is that there have been random occasions I'll check when the signal strength will tell me it's strong, then it'll drop off again within seconds. 

On the subject of support, in my searches of the forum, I know what you mean. Many threads I came across seem to have just fizzled out. 

  @ConcernedUser 

If another manufacturer made outdoor Mesh nodes at the time I bought the X50-Outdoor, I would have changed to them. TP-Link's biggest failure by far is the lack of good support. Just ignoring a problem (read customer) is not going to endear anyone to a brand. Once I am a bit more flush, I will be moving to Netgear who now have outdoor Orbi nodes for the simple reason I spend too much time administrating my Deco network.

Pushing wifi through thick walls and new-build houses that contain foil-backed insulation will always be a problem, solved really only by using Backhaul, but for most this is impossible unless you use Powerline Adapters or PoE Deco. But most houses cannot be retrofitted neatly with ethernet cabling, Powerline is the ideal option, but when I tried this, nodes kept going offline for no apparent reason and my request for help on this forum went unresolved.

Most improvements in wifi are that of speed, not distance. There are federal/local authority limits on transmission power and all the fancy antenna arrays don't change much, if anything. If I started again, I would probably stick with M5 as they have the separate IoT network and would hardwire the TV from my media server so that the wifi only tackled the internet connectivity for devices that need it, reducing the need for overall speed.

To prove to myself the distance thing was not in my head, I took my cheapest Deco node (an E4R) and replaced the X60 that links to my outdoor Deco. The X60 shows a poor signal (sometimes Medium), the E4R shows the same. So much for the X60 tricksy antenna array!

  @SteveWex Interesting. I don't need an outdoor node, but I have just learnt about EasyMesh routers. I wonder if, with those each being dedicated routers for boosted coverage, they might work better than the Decos. I've seen a WiFi 7 easymesh router go for around £50, whereas if you want a WiFi 7 Deco, it's almost 3 times that. 

I also don't have the option for backhaul, considered TP-Link's powerline series like the PX50 but it seems very hard to gauge if it will actually help my issues and improve latency.

In terms of distance, I guess you're right. Most Decos I've tested have a similar range and it still seems as though my S4 is one of the better ones. But given they mention higher ranges on the box, I thought there were at least some leaps in coverage possible. Do you find your X60's at least covers a larger range, or gives WiFi where the E4R might not? 

Currently a single Deco units provides about the same range as a Virgin Superhub3 in my testing, which is a router widely known for being pretty bad. But I guess ranges are similar across all routers? 

I never used IoT on the m5's, wonder if I'm missing out. I am bummed on the X60 because they're the one model I figured might actually have increased coverage and signal strength. I have noticed some Decos giving that slight bit more than others, like my Deco S4 covering the garage while the M5 would not, just hoped X60 would be better than all of them at least. 

Again thankful you shared your experience. I'll know to temper my expectations even if I do get the X60 because I don't reckon signal strength will change. Perhaps they might help maintain top speeds throughout the house but that's it. Wonder if it's worth the upgrade when WiFi 7 is taking off and they lack it. Still, being able to trade in the M5's for them seems like a good deal at least, even with the extra cost.