I have a couple of pair of Performance Gel bibs.
On the upside, they're super comfortable. I'll wear them almost exclusively for several rides after wearing my tukus to a pulp on a fast century or something.
On the downside, they are surprisingly heavy, relatively speaking. I you wear bibs, the real drawback is the top/straps are made of the same material as the shorts... I'd like something lighter in hot weather. If you don't wear bibs, the weight difference is completely negligible.