I'm a stepin guy, but I can help a little bit. One of the things you'll be interested in for freestyle is to be able to set your forward lean to ZERO. This can be helpful on the rails. Other things you might want to consider is how sturdy the parts are. There's nothing more annoying than cheap parts that are going to bust loose under a beating. There are different grades of plastics. Metal is nice, but can get ratty looking after abuse. Take a close look at the ratchet mechanisms. Cheaper ones can freeze up with snow and some are hard to work with gloves on. Pay close attention to where the straps are located. Some people swear by toe cap straps, some people swear at them. Look for adjustments too. You may want to be able to micro adjust your stance width. Having a binding plate with slots instead of holes gives you a little more flexibility. Some bindings have heel cup or other adjustments you can make to give the binding a better grab on your boot. The bottom line is that you're looking for a tight fit in the bindings so there is no "communication gap" between your feet and the board and a sense of "power transmission feel". The gap is a function of fit. The feel is a personal thing.
There are so many different brands of snowboard gear, I'd imagine that it's hard to find people with experience with specific gear. But this is the Internet and we'll probably find someone eventually. If not, you can always be the first to report back with your experience!