Been with virgin since 2001, Never had any serious problems, Customer Support seems reasonable allways got it sorted in the end. Was originally on 20meg but upgraded to 50meg when it was in my area.. And to be hounest ive never looked back its worth the extra money to get the 50 in my opinion. No traffic shaping, Speeds seem to be consistant for me regardless of what time it is ping times very low as you can see from speedtest as low as 5ms.
Some mug deicided to cut my virgin line outside my house couple of weeks ago it was sorted next day allways been sharpish for me =)