Like the eternally debated GI spring guide/FLGR thread, the bull/bushing ends the same way, nobody can sucessfully advocate one to the exclusion of the other. Bulls have potential to be more accurate than bushings, which is counteracted by the fact that a real professional bushing fit can run the weapon as accurately. Only the bushing wears along with the barrel such guns whereas the bull reacts against the slide, but aside from the amount of ammo neccessary to do this (if you can afford X rounds, you can afford to replace Y argument) One can easily fit an oversize bull and the problem is solved. It can all go back and forth for a while. There are 2 indisputable advantages of bulls, those being fewer parts to break at a critical moment and more weight at the nose than a bushing barrel, but the former is a very remote possibility, and the latter can probably be compensated with the addition of a heavier FLGR if necessary.
I have both. I like both. The Bull barrel really generates praise from me on my 4" compact, which makes perceived recoil more akin to a 4.25 full-frame Commander, rather than a 3.5" compact Officer. I wouldn't be averse to one on a 5" .45, but I probabably wouldn't go out and buy/build a 5" bull either. Now in 10mm, we'd probably have a different story. Pick whichever you prefer. Each has its own advantages.