I'm currently spotting with my 100-400 lens but I happens way too often that 100mm are to much!
This is why I wanted to expand my equipment.
I was looking at three different lenses:
Canon 24-105L > is very expensive,but worth the money?
Canon 17-85 IS USM > I heard that this one has some problems at 17mm and the colors are not that good
Canon 18-200 IS > less expensive than the L , but a large range of zoom (loss of quality?)
I would use the lens on a 450D and a 60D.
Thanks in advance!