Not as much since they're designed to handle axial loads as well as radial. Typical cartridge bearings are really designed to handle mostly radial loading, and unless the alignment is spot on and stays there (I don't think the PF30 Nylon cups help in that regard...most likely flex during use, especially on the driveside) they're going to fail early.

It seems to me the combination of the aluminum cups and the angular contact bearings just makes a ton more sense for a BB application. The one I have in my S5 has well over a year and 5000 miles of trouble free operation so far.

edit: BTW, the old "cup and cone" style BB bearings are basically angular contact in design ;-)

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