I started at PS, and srtill like it best. UB I find boring, with little in the way of graphics, but I play there quite a lot. I find the cartoonish avqatars at FTP a bit of a distraction, but the poker is usually good there, too.
Actually, I"m not crazy about any site with the avatar system,eg: FTP,Cake,Doyle's Room, etc; I think that sitting at a table with 3-4 players wearing the same face kills concentration.