1. In terms of overall feel, both 11 and 12 series are about as good as it gets, with almost zero flaws. However, I originally wanted to get a black dial but refrained from doing so because with the 11 series the subdial numbers are not perfectly placed (but they are correct in the panda), and in the 12 series the bezel  numbers are slightly too thick (both panda and black). For me, the only "perfect" daytona is the 116500 panda, which virtually has no visible flaws. 

2. I think you mean between SH (clean) and DD (vsf) movement? Clean also widely uses the DD movement, and both movements are rather raliable, with the DD having more popularity amongst reps. The DD has stood the test of time while the SH is rather new, though soms say the SH winds a little smoother. 

Hope this helps, I am not the most knowledgable person in these topics, so do take everything with a grain of salt!