Ok so virgin media uses Fibre to the Cabinet (FTTC) then normally its Coax to your house. I haven't ever heard of Virgin media running fibre to peoples houses unless you are running a lease line or a business package.
Jitter / High Pings and a few other problems that virgin media has is normally down to how many users there is in the cabinet / exchange, the higher the users the worse it is. If its a low populated area with a fresh exchange / cabinet then you should get good speeds and good response times. Virgin suffers like every other ISP in the UK with problems here and there.
Use
Sam Knows for services.
I've been with Virgin Media for 7 years now and apart from the odd problem its been pretty rock solid, i use to have 152Mb/s but i downgraded as it was like £65 a month. Now i'm on 72Mb/s