Originally Posted by ADSR

For what it's worth, Campagnolo is rebuildable, SRAM and Shimano aren't. Granted, the only two gruppos I have meaningful experience with are Shimano 105 (5600) and Campagnolo Veloce from 2009, so I really can't speak to the quality of the higher-end merchandise, but for what you're talking about I doubt you could really go wrong.