[the3dge]

Canon EF-S 17-85mm f4-f5.6 IS USM
I recently uprgaded to a Canon 50D with an EF-S 17-85mm f4-f5.6 kit lens included. Although I got a great price on the kit I'm not overly impressed with the results that the lens has produced, quite a lot of distortion at 17mm and fringing on verticals, when compared with my previous Nikon and Olympus kit. I'm thinking of changing it for something a bit better, hopefully!

Should I go for the EF-S 17-55mm F2.8 IS USM, EF-S 15-85 f3.5-f5.6 IS USM, or would I be better going for the EF 17-40 f4L USM. I'm unlikley to be upgrading to a EOS1 or EOS5 in the near future so the EF-S mount is not a problem. Any recomendations?

Thanks in anticipation.

The3dge!