@David-TP hi, I noticed because the app "eWeLink" kept telling me devices were offline. As I then walked around my house I could see my light switches were disconnecting and reconnecting as they have network indicators on the physical devices. They would be solid for about 30 seconds (meaning connected) then start flashing to indicate lost connections. 
 

I only set up my decos last night, I have not yet enabled the IoT separate network, I was enquiring about it because I wondered if perhaps it might help the issue if I had a dedicated IoT 2.4ghz network. 
 

if I disable "mesh technology" for devices, how do I ensure they're connected to the strongest signal/closest deco?

  @David-TP oof, just to update, been monitoring today and so far I'm so disappointed! I bought these to make my WiFi *BETTER* but they've made it worse!

My house is only 80m2, with a 70m2 garden.  These should be far more powerful than I need, but a) none of the smart switches will stay connected, b) I am in my garden, less than 1 meter away from a deco unit in my house - I can almost touch it! There's no walls in the way as such since the back garden is accessed via a huge bi-folding door that opens almost the entire width of the house and yet can not pick up the WiFi! What the hell am I doing wrong?? 
ALL Decos are on the latest 1.2.0 firmware, AP Mode, Smart DHCP OFF, Beamforming OFF, Fast Roaming OFF, and the ESP Devices (light switches) I've disabled the Mesh Technology and it's still awful.  I had better wifi with just my single Asus AC86U Router :(

I've obviously tried with beamforming and fast roaming ON etc, Ive tried all combinations I beleive.

When I was using my AC86U as wireless, everything connected and stayed connected, but the position of it meant wifi was weak out the front or in rear garden.  I disabled WiFi radio on the ASUS AC86U router so it's ONLY acting as a LAN Router, The Deco trio are the only WiFi network enabled and as I say, the WiFi is WORSE 

I had installed a 3 pack with v1.0 hw version, and now I have purchase 2 more decos x50 with v1.2.

I have a lot of problems with IoT network because it is not supported by old firmware, so I wish the ETA of new firmware be as soon as possible.

I cant understand how TpLink has not released the same firmware for the different hardware versions at the same time. That is not serious for a first-class brand as Tp-Link. Very dissapointed by now!

  @David-TP 

1) There are 16 IoT devices

2) I still haven't tried dedicated IoT network yet as I haven't had time, however I will be setting this up this afternoon and reconnecting all IoT devices to the dedicated IoT WiFi

3) Currently, my "Main" Deco (X55) is connected directly to my Router.  The 2 Satellite Deco's (X55) are connected via Ethernet directly to the "Main" Deco using the 2 Ethernet sockets.  So all 3 Ethernet sockets on the "Main" are in use.  1 going to router, the other 2 going to the other 2 deco units. 

As I understand it though, because I am using Access Point (AP) Mode, I should be able to connect each deco directly to the router?  Is that correct? From what I've read I believe I should be able to connect each one direct to the Router LAN Ports because in AP mode, the Deco X55 units are all equal there is no need for a "Main" ? 

  @David-TP another update. Literally getting nowhere. I've spent far too long on these but they're clearly useless or perhaps mine are just broken. 
 

I've created a dedicated IoT network, 2.4ghz, I've turned off mesh technology on all IoT devices. They still keep disconnecting!! I've never had such a bad experience. 
 

At this rate I think I'm going to have just return them and get my £200 refund and go for Amazon's Eero instead we had those at previous house and worked with all these devices perfectly. The eero wasn't mine so couldn't bring with me to new house. The Deco X55 was cheaper than 3 EERO's but honestly not worth the headache. So disappointed 

look at the picture attached, despite it being so close it still won't connect, or if it does, it's only for 30 seconds ish then disconnects again. Even on dedicated IoT network. 
 

I have to repeat also, my ASUS Router, when WiFi was enabled, was 1000% better and everything connected perfectly. My issue was poor signal, but the decos have made it worse and now I've got poor signal, no signal in garden, devices disconnecting, iPhone keeps dropping connection etc. I just don't know what else I can do. 
 

and 24+ hours between responses isn't good enough when the device isn't working as intended 

  @David-TP Hi, someone only reached out to me about 1 hour after your comment above.  Now the problem is the 8 hour time difference!

EDIT: Scrap that, I've had enough, I've sent these back to Amazon today.  Sorry, but these were absolutely useless and just did not work for me.

  @David-TP 

Hi, good news regarding VPN support

Could you please confirm this scenario would work:

Existing setup:

(ISP Modem) -> Deco X60 Router -> (ethernet backhaul) ->> (2 Deco X60 Satellites)

I would like to puirchase another "VPN AP" by connecting an X50 to one of the Deco x60 satellites

Proposed setup:

(ISP Modem) -> Deco X60 Router -> (ethernet backhaul) ->  a Deco X60 Satellite -> ethernet cable -> Deco X50 (VPN) -> Smart TV via Wi-Fi or Ethernet

I do not want to route all my traffic through the VPN, but would rather setup a new VPN-only Wi-Fi Network by configuring the new Deco X50 to use a VPN service.

Would that work?  What worried me is that you mention not all new features will be available if the Deco is in the AP mode.  I wonder if I could still configure VPN on a "Satellite" Deco in AP mode and continune using the "Main" Deco X60 as a router.

Thanks