Im going to agree with everyone above. the 17-55 2.8 is the best option for the 7d. I just bought the 24-105 since I have made the switch to a 5dii for general photography. I can tell already that the 2.8 and IS together will be missed in low light situations. I will also agree that the focal length range of the 17-55 is much better for general photography than the 24-105 on a crop sensor like the 7D. If I were still using my crop body for general photography and indoor phototography I would never switch my 17-55 for a 24-105. With that said. I may be a bit biased because Im going to end this post with saying that my 17-55 2.8 is still for sale if you are interested in going the used route to save a few bucks.