I like the R4 plate. In my opinion it offers both an effective and a pleasantly smooth shave. Though I get good shaves from every other plate as well - but R1 is too mild for my taste
I haven't tried any other than #2 and #4, but I know I like the #4 for longer stubble, but for everyday use I get easy BBS from #2. Can't wait to try the others. In time, in time.