If you are talking about the standard 7/8" bars IMO the Pro Tapers SE's are the better built of the two. I just put a pair on my bike, they are priced very competitively also.
For standard bars I really don't think you can go wrong with either one. I had Renthal 7/8's on my XR200R and they were great. In fact, they're still on the bike after 3 seasons of riding. That said, I've heard nothing but good things about Pro-Taper handlebars. They make a quality product.
For oversize bars, I really think Pro-Taper is the best on the market.
