I know the WD Blacks get the nod as fastest non-SSD drive, but I prefer the F1s (1tb) for my OS drives. Main reason being they're very quiet while being plenty fast. I try to keep my systems as quiet as possible and the Caviar Blacks were noticeably louder.
I do agree that Samsung's RMA process doesn't seem so hot (going through vendor instead of Samsung) but I haven't had to deal with this yet, and hope I never do.