BFilter does not collapse anything. It does a superb job of blocking ads but you will have grey frames all over the place. I'll leave out my views of Pithhelmet which are not all that favorable.

OW's built-in blocker along with a simple css style sheet get's rid of all ads and about 50% of the frames on my install. Other than 3 Yahoo! specific servers I've added, the 3 filters OW provided appear to do everything I need.

Using Safari with SafariBlock get's rid of 99% of the ads and the frames about 80% of the time. Highly recommended if you use Safari as well.

There's no perfect browser but if OW could collapse all banner frames it would be as close to perfect as I would want.