I Currently have a Canon Digital Rebel XT and have an opportunity to get a fairly inexpensive, used Canon 10D. I would have to get rid of my XT, so I won't be able to keep both. In addition to general photography, i take many sports photos (Volleyball, basketball, softball). I do have some very high quality glass to go along with this basic body. Will i see much of an improvement between the 2 cameras in performance, especially when it comes to the focusing speed? I think the 10D writs a bit slower to the CF card. Comments from anyone with direct experience with both cameras is appreciated.