Really, Longlaner? That's quite an accolade, given we've got so many restaurants around here.
(I've only been to Tentazione once. Food and service were v. good, but atmosphere was a bit low key for it to the best in SE1 - rather than "really good in SE1" - imho. I'd go there again happily, though, if anyone wants to invite me. Even more happily if anyone else wanted to pay ;0))
Best restaurant in SE1 would make a good thread topic though, don't you think? (I think I'd vote for Blueprint Cafe.)