Originally Posted by masi61
One of the things I like about cartridge bottom brackets is that the cartridge and the adjustable locking cup are hidden, leading to an extremely clean look at the bottom bracket. This cleans up the look of any bike. Fixed cups are a pain to remove without fear of scratching the paint on your baby. I guess you could purchase one of those expensive Stein fixed cup tools that locks the tool on to prevent that. The adustable cup and lockring side attracts dirt and the tools required aren't standard from brand to brand. Usually I can rebuild most brands decently, but I must add my name to the "cartridge bottom brackets are great with no negatives" list.
+1
Yet another point in favor of cartridge BBs: the BB shell does not ever need to be faced precisely. This reduces manufacturing/assembly cost. Facing was often necessary on high-end frames with cup-and-cone BBs because the threads must be aligned very precisely in order for the bearing to operate smoothly. With cartridge BBs, misalignment of the threads does not affect the alignment of the bearing (to within reason!).