Being bigger means he'll draw more fire, and the vast majority of your enemies won't have AP3 weapons.  The biggest drawback to a light power armor suit is that you won't get a void seal, and the suit isn't as compatable with upgrade systems like magboots.  If you're okay with that, then you can dodge slightly better.<br/><br/>Of course, I think it illustrates my attitude perfectly to say that I'd offer you a set of Soriatas power armor if you wanted to go the light power armor route.  :P