Urethane is being used in the highbacks of bindings (ie. Flux) to give a looser and more flexible feel. its more of a freestyle thing. If you like charging, stick with a traditional composite high back which will help with your edge to edge power and SPEED. if you jib all day all night... think about it. The best advice when ever you are thinking of grabbing new gear is to demo it first. Look up on companies websites when they are doing product demo days at local resorts and hit them up, or talk to shops. Some shops have a performance guarantee that will let you bring gear back for an exchange if you decide in the end you hate it.
sounds good ill check them out then at a demo or try that preformance guaruntee thing