I think I'm going to have to give VM the boot. The only thing that's been stopping me is the hassle this will involve because of the location of my old, currently disused, BT master socket. The VM socket is in my lounge, which is ideal, because that's where I want my phone base station, and my Ethernet infrastructure is based around it. However, my BT socket is in the hall. Do any of the main telcos give you the option of installing a new socket where you want it? Do they charge extra?
If I have to DIY some cabling from the original master socket, would it be better to use a single extension and put the filter in the lounge, or have the filter in the master socket and two separate cables? My old master socket has a built-in ADSL filter installed by BT in the early 2000s back when the max speed was 512Kbps and you had to use a USB modem that looked like a frog. Are those old filters suitable for modern broadband speeds?