Yesterday, I traded in my Canon EF 70-300mm f/4-5.6 IS USM lens at my local Penn Camera, in Rockville, Md. I was never happy with the lens, which focused slowly and produced too much noise. Yes, I know the photographer is always to blame. There are bum lenses sometimes, too.
As result, I relied mostly on my Canon EF 24-70 f/2.8L USM lens, which dramatically changed my shooting style. When I had the Nikon D70, I liked to hang back, typically relying on the Nikon 70-300mm f/4-5.6D ED AF Zoom-Nikkor lens. The Canon L lens means getting in closer.