I'm riding BB30 now. I think, for low-mileage, low-usage bikes, it's not a big deal. (Witness the folks with a half dozen BB30 bikes with no problems.) BB30 IS very quiet and smooth when you first install it in a frame. I like the ready accessability of high-quality bearings. I don't mind the installation issues -- although it is messier and more of a hassle than external bearing BBs. Q-factor? It's a non-factor. Marketingspeak. (Did you REALLY have trouble pedaling before??) Lighter weight? Wasn't true. Isn't true. Marketingspeak.

What I don't like is the introduction of the plastic between metal and carbon fiber. This provides a new place for creaks and wear where there wasn't any before. And, since it's plastic, it's more likely to creak and wear than anything that came before. The crank might be stiffer, but the total system probably isn't -- after all, you've got soft plastic providing a tiny bit of give -- a flexpoint.

I'm riding it. It works okay. But external bearing BBs are better on a number of levels. Adapters don't solve the problem. BB30 isn't engineering -- it's from the marketing department.