Replying to STH differences

I tried searching for a thread like this, but couldn't find one that exactly answers my question.  I recently purchased the 2012 atomic punx (173cm).  Im purchasing bindings soon and am lookings at the Salomon STH series.Besides the differences in weight, what are the advantages and disadvantages between the STH 16, the STH 14 Driver, the STH 12 Driver, and the STH oversize.  Which one would you recommend for me?  I plan on skiing 80% park.  im 5'11, 181lbs.   The way Salomon explains them on their website is kinda confusing.  Thanks!