@InfiniteRiddle 

Deco cannot be used as Range Extenders, nor is it advertised as such.  Deco is a Whole-Home WiFi Mesh system.  It takes multiple units with the same configuration and links them either through a wireless or Ethernet backhaul to create a single unified network.  From there strategic placement of the units can provide you with a full home coverage for your WiFi.

The Deco M4 does have 1 Gbps ports so it should have no issue working with the service.  If you would like we can help troubleshoot and get them working as designed or at least give an explanation for the issues you may be experiencing. 

  @MikePCTECH 

Mike AP mode and Range Extender or RE mode are two completely different things.  Range Extenders do just what the name says, they extends the range of the existing wireless network. APs or Access Points are something different.  When you run a product in AP mode you are disabling all advanced and router-specific features and only makes use of the Wireless feature in the product.  This still requires one unit to be physically connected to the router or gateway that exists on the network.  It creates a separate WiFi network.  Since it does not extend or link into the existing network it is not a Range Extender or Range Extender mode.   

I just want to make sure that is clear for anyone who might come to this thread and assume the product can do the things of a Range Extender because it cannot. 

  @InfiniteRiddle 

Nothing I said in my first response was untruthful.  Deco products cannot be used as Range Extenders.  They are a whole home Wi-Fi system and they all have the same configuration. This is how any of the units can be designated as the main unit and then connected to the modem and the network without reconfiguration will still work. Deco units can be connected to each other through wireless or Ethernet backhaul,  All of that is true.

Also, the Deco M4 does have gigabit Ethernet ports so it will work with a 1 Gbps service provider.  Your getting only 300 Mbps requires troubleshooting to determine if there is something wrong with the product, a compatibility issue, a limitation on a client device or just something you set up wrong.  This is the reason why companies like TP-Link have a support team.  So we can be available to assist customers when they encounter concerns with products.  

I understand your frustration but comparing a $149 dollar product to a $500 dollar product is really like comparing apples to oranges.  Of course, the $500 dollar product will be more feature right and likely perform better.  

Again, if you would like to troubleshoot your concerns related to speed and performance we would be more than happy to assist. 

  @MikePCTECH 

I absolutely get that.  I just wanted to draw a distinction between REs and APs and that one unit always has to be connected to the source, so that the non-technical customers are not confused   Your description of how Mesh blankets a home with WiFi was a good description. 

  @MikePCTECH 

With Verizon, your "modem" comes in two flavors.  1. If you just have internet service it's likely an ONT that the fiber comes into and then an Ethernet out to plug the router into.  And a gateway if you have FIOS TV service too.  

If you have the gateway a potential cause of the speed performance could be double NAT if you are using the Deco in router mode.  Unfortunately, the only solution for this is to put the Deco in AP mode which eliminates the double NAT and usually clears up the speed concern.  

Now it is worth noting that some of our WiFi 6 and 6E Decos recently had a concern with Verizon resolved in firmware.  The Deco M4 was not listed but I will be checking with the software team to see if that could be the cause of your concern as well.