Comments about SRAM SRAM GXP BlackBox Ceramic Bottom Bracket:
This is a very nice, very smooth bottom bracket. I think I can actually feel a difference from the metal bearings. SRAM however recommends maintenance every 100 hours or after riding in the rain. They want you to disassemble the crankset, remove the seals, clean the old grease out and replace it. I've not done this yet but it seems excessive to me. I've ridden a DuraAce BB for years at a time without maintenance with no problems. If you don't mind the high maintenance, it's a great BB.