@terziyski Cheers for replying but was after an answer to a specific question rather than a load of meterial which may or may not contain the answer.

@madebyDBM 

These documents could help with terminology, putting everyone on the same page. They also provide general understanding of technology and its limitations. If you are considering TP-Link Deco, it'll help if you read them. If you are new to WiFi mesh technology, these documents give good overview of it.

If you wanted just an answer, here it is: "Yes, Deco is true WiFi mesh, according to WiFi mesh definition. Yes, each of the satellite units prefers to connect to the primary unit. Currently, for Deco P9, there is no ability to manually overwrite satellite unit decision of which unit to connect to."

Also, specifically for Deco P9. This is the Deco unit which can use powerline backhaul. Here is more information on it: General Questions about the Powerline or PLC Backhaul Feature of Deco

If you know you can use powerline backhaul in your house, P9 could be a good choice. Also, with powerline backhaul it is less of an issue where satellite units connect to.

In case your place electric wiring and/or P9 units location can't utilize powerline backhaul, Deco P9 may not be the best choice. If you like P9 form factor, you may wish to check Deco M4 or S4 instead. They have similar specs to P9, but won't use powerline.

Note that P9 will prefer powerline for backhaul, even if electric wiring is of inadequate quality. That means, worst case scenario you'll get really bad speeds on WiFi devices connected to Satellite P9, even if WiFi signal from WiFi device to Deco Satellite unit is strong.

In case your Internet connection does not exceed 100Mbps and will not in the future, Deco E4 could be better choice. It is as good as M4/S4/P9, but it has 100Mbps Ethernet ports instead of gigabit, limiting internet connectivity to 100mpbs. Deco E4 should be least expensive among P9, M4 and S4 units. 

Finally, out of all Deco models only Deco M5, as of today, allows user to define where Satellite unit will connect to, currently in beta firmware that needs to be installed on units manually. If you want TP-Link Deco mesh, can't use powerline in your place, won't be Ethernet wiring Satellite units, must have ability to configure Satellite unit connection - consider Deco M5.

@Alexandre. 

Hi Alexandre, thanks very much for your very thorough reply, it's much appreciated.

Must admit I am a bit surprised about the configuration - I'd have thought satellites connecting to each other rather than all back to the base unit would have been the norm and preferable.

Thanks too for explaining the differences between the models, that's very helpful and has made me question whether the P9 is the best system for my needs.

Thanks for taking the time reply.

All the best, Rob.