No complaints here either. Was on Virgin Media 2Mb cable service. Now on O2 & also get around 12Mb. O2 is ADSL2plus to Tiscali's standard(?) ADSL - perhaps that makes a difference to the excellent & consistent speeds.
I don't need my extra speed either - getting 6 times the speed for £2.50 a month less with O2. Also a wireless router & free UK 24/7 phone support - neither of which I had with VM. Couldn't be happier :-)), G