I made the jump from PlusNet to VM last October when VM installed their FTTP (RFoG) in our area (as part of Project Lightning).
On 350Mb broadband tier, and finding it at around 290mb over WiFi (don't have a hardwired LAN device) I'm pretty happy.
You just have to be on the ball when your initial deal ends to ensure you don't end up paying almost double the initial monthly price. Call wait times can be long - but that does depend on WHEN you call.
Support isn't always great, depends on who answers the call (suppose thats the same with all ISPs).
From an Install perspective, as ours is RFoG, civils guys ran the fibre under the lawn, they do prefer to run straight lines, so wont wiggle around the garden. I had read horrible stories about them leaving cables above ground instead of channeling out the concrete, however that wasnt a problem to those particular civils guys, they channeled out around a foot of concrete path to keep the install clean. They said they would have done a channel down the entire driveway if it was required...
Go-Live day, a local guy came and did a quick survey, asked where I wanted the TV box, but said I wanted the main Router in my Office, this was a bit of extra work for him, but he was happy to oblige, and ran a spur of Coax externally into the lounge (we're in a bungalow) for the TV box. He also left me plenty of spare cable in the office to move the router around as I asked him to.
I don't use the SuperHub 3, its a bit pants, so I'm running my own Router, using the Hub3 in Modem Mode.
We never get any buffering (unless I'm downloading large files), even when streaming multiple HD streams (Prime, CatchUp Services etc).
I'm in Doncaster, so all I would say is that speeds can be affected by network utilisation, so if your area has had VM for a long time, your experience may differ slightly
Regards,
Haydn