Summary: This flash (purchased at B&H) worked nicely on my rebel xt. It is compact, light and uses only 2AA batt. When I got my 40D it would not sync. Called sunpak and I sent it in. They said ther was no upgrade for software so sent me a brand new flash that isnt even seen in stores and it did not fire with my 40D either. Sold the flash and bought 430EX just because I knew it would work.
Pros: Consistent Output, Durable, Easily Interchangeable, Easy To Clean, Fast Recycling, Lightweight