Hello:





My current equipment consist of Canon 50D, EF-S 10-22mm, EF-S 18-200mm, EF 50mm 1.8, EF 100-300mm. I am planning on eventually upgrade to full frame and get the EF 70-200mm. I am not very satisfied with the EFS 18-200 so I want to upgrade. I am considering the 24-105mm, 17-40mm, or 17-55mm. Any thoughts on which one to get? I am leaning towards 24-105 but the f/4 is throwing me off a little. Any help will be appreciated. Thanks