Saw both casts last night and I overall preferred Miller's creature, with a couple points that Cumberbatch did better, though both were just fantastic. The opening birth scene I overall preferred cumberbatch though at some point it just felt overwrought as well as the closing scene I preferred cumberbatch, but for the rest of it I preferred miller as the creature. He did a much better job with the creature's rise as Frankenstein fell.
The music and overall production makes it VERY obvious this was a dry run for the Olympics. Lots of reused sounds and ideas and familiar set stylings from both Boyle and Rick.
After the first showing I heard the pair of Cumberbatch/Sherlock fan girls (most of the crowd fit this description... :/) behind us say they were gonna get the soundtrack.
Hearing someone say, "The director is well known, I think, He got an oscar and did the olympics in Beijing." in the lobby between showings made me cringe though.