[Jacquesb]

After a bit of research, I decided to stick with Powerline adapters and ordered a set of 3 from TP-Link.

I purchased the TL-WPA4220 set which arrived same day & installed easily giving good WiFi reception in extension/conservatory which was previously a very dead spot. I actually bought the 3 pack as I have some wired devices in a bookcase, but the WiFi from one of these adapters is actually fine - even behind the books in the bookcase, so one adapter is actually redundant.

Very pleased, BUT !!

My router (Virgin Superhub2) has WPS disabled so I was unable to clone to the main SSID and password which is a bit of a bore as this was one of the main selling points for me. TP-Link support sent me a link for the download of a MAC app called Wireless PLC Device Scan which fails to find any devices at all on the network, although the tpPLC app on the same MAC sees the devices okay but doesn't let me change anything.

I've emailed back to them + await a response. Anyway, thanks for the comments - I'll update if there is any change.

On speeds, I ran a couple of speedtests:
(1) in the same room as the router, using 5G, the results were 9, 101.86, 12.58 for ping, download & upload.
(2) in the extension, with the TP-Link powerline adapter, the results were 11, 35.95, 12,51.