**Update**
So after having the Deco units setup for a little while I can attest that the performance is excellent on the Wifi and I am getting 910Mbps Down & 886Mbps Up, on my laptop. So I am very pleased with the speeds I am getting. The mesh on the Deco also seems consistent and stable as I have not had any drops or outages and roaming around the house is seamless and there is no disruption that I can see when your device is handed over from one mesh node to another.
However there is some alarming downsides to these units that you will only discover upon purchase as it is not made clear on the product page, nor was it really bought up in the reviews.
1. In order to setup the devices you are forced to create a cloud account with TP Link. Yes that's right...You can do NOTHING with these units until you are signed up. Furthermore, there is likely usage statistics data sent back to TP Link.
2. Setup and management of the units are done through the phone app ONLY. See point 3 for more detail.
3. The Web UI is completely gimped offering only the very basics in router/AP management as TP Link have decided to force users to use the phone app.
So if you are expecting to have a full web UI management experience with the Deco series, it isn't going to happen and furthermore the phone app while certainly offers most things are missing some features you would inherently expect including but not limited to things such as Backup/Restore, MAC whitelisting, Manual Wifi Channel Selection. Granted, they are actively adding new features to the app, so hopefully in time these will be included.
There (rightly) is a large complaint thread on the TP Link Forums from hundreds of users demanding a proper Web UI interface as there a multitude of reasons why management via a phone app is untenable. I also posted my concerns. Unfortunately it is TP Links stance that irrespective of consumers complaints they are going to stay the course with the phone app...which is complete madness.
You can see my complaint as posted below.
So in summary, these are excellent devices so far as the hardware and the speeds achieved and when used in AP mode, the lack of a Web UI is not a killer issue, hence why I have decided to keep them. However in router mode I could see that managing these devices would be an absolute nightmare.
Can I really recommend these to others, realistically no...for all the reasons above and per my post on the TP Link forums.