I'm replacing the Ultegra bottom bracket on my 2000 Trek 5200. I have not purchased a new one yet because I have several questions I need to get answered first. I was going to buy another Ultegra BB of the same part number to keep things simple but I have a few twists that may not make it so simple.

1) I plan on replacing my 9 speed Ultegra drive train with Campy record (10 speed) but I want to keep the same cranks. One of the companies that makes the Shimano-to-campy conversion cassette says that you can convert and keep the same cranks/chainrings and front derailleur. I'm not sure if going from 9 speed to 10 speed will require a different bottom bracket though. I'm only replacing the rear derailleur, chain, shifters and cassette.

2) Will the newer bottom brackets with external bearings work on my frame? If so should I get the newer bottom bracket?

3) Since I've been searching the web for bottom bracket information, I've seen a lot of info on ceramic bearings and how much better they are than the factory Shimano stuff. Is there really that much difference? I'm not an elite cyclist so not sure if I should consider upgrading to a better BB.

Thanks for any help,
Andy

Bike Nashbar has the original Ultegra BB on sale for $55.