The winged highbacks are a total gimmick IMO. They were popular during the 90s and faded out, and are now back on T9 and the Infidels. They are supposed to help you press easier, but in reality it's more of a fashion thing than anything. People were able to press just as easily when they didn't have the wings, and the fact that the wings are on the outside, rather than the inside helps fuel the thought process that it is just a fashion thing.
Think about it, when you press, you pull up on the opposite leg, so the wings should be on the inside as they can give better leverage there, rather than the outside. Some people like them, some people don't. It's your call on whether you want to use them, but IMO they don't really add much to your riding.
I have Forces and love them. Best bindings I've ridden, and they hold up to abuse really really well. I've never ridden the 390s, but have heard nothing but good things about them. You can't go wrong with either binding.