I failed to mention the slick skin and the flexibility of the suit, like Steve mentioned. I wouldn't even bother getting a suit without both. It might add some to the cost, but man, it's worth it, imo.

Before the flexible material came out, I use to fatigue really fast, even just pumping up the kite. It was ridiculous.
The slick skin makes a huge improvement on keeping the wind from blowing thru the neoprene.