I use the 24-105 for weddings but on a 5D. The high ISO performance with the IS allows me to get some great shots when I can not use flash. I am not comfortable with the high ISO performance of any of the APS-C bodys with the possible exception of the 7D. I have used my 24-105 on my XTi and find it sometimes not wide enough. If I were using an APS-C body i would go with the 17-55.


Mark