It's a tough call. I like seeing Batman as flexible and movable as possible, and the new suit allows him to move much better. But the old suit looks more like Batman to me. Take away the cape and cowl and the TDK suit could be any high-tech military outfit -- or extreme motocross gear. Practicle yes, but also too busy. I like the sleekness of the BB suit, but not the fact that he can't turn his head. Yet I don't really like how the TDK suit looks from behind, with the long neck and low cape. The BB looks a lot tougher from behind, with the thick panther neck and the way the cowl comes down is very classic Batman.
Both figures are out now and I have yet to buy one, but am leaning more towards the BB version.
While the film version of the TDK suit is certainly more flexible, I imagine both suits nearly identical on the figures, except for the neck area, aren't they?
Having said that, I haven't seen the BB figure posed throwing those high kicks like the TDK has . . .