Hey Guys, thought I would post one more time on this thread. I ended up finding a mint condition 70-210 3.5/4.5 USM lens on Ebay that I picked up for $250. It is a great big brother to my 28-105 3.5-4.5 II. I haven't played with it much as I just got it, but the USM is dead silent and snappy on my XTi. Thanks for your help!