Obviously the 4xx would be better, or at least you would think so being a higher version number. Not always the case with RIM OS's. Besides as the previous poster stated there is nothing higher then .337 out right now so you have no choice.
yea, usually the higher OS's are "improved" over previous ones. but then again, ive seen some OS's actually are worse than previous releases. also, what works perfect for you, may not work well for my phone. its hard to tell, as for some strange reason, some OS's work well on some devices and not others. the only way for you to know is to load it up and test it out for a few days.