I have a 7D and a 10-22mm EF-S, and I am pleased with the overall quality. Center sharpness is very good and corners not too distorted or purple fringed. I also have a 5D II, but apart from the 15mm fisheye, I do not have a really wide lens for that camera. What you do need to bear in mind is that you are only going get really wide images on your 7D with the 10-22mm - you can use the 16-35mm on it, but it will not be as wide. It really depends what you want to get with your surfing shots.