Hi, Just bought a canon eos rebel t2i-550D(18-55mm IS kit lens). Was a pain in the ass to find but i got my hands on it. I've been shooting for the past few days, and iv compared the pictures to my friends Canon 7D. Really no difference. Iv been looking around for some new glass, especially since my friend had just purchased a 17-40 f/4L USM. Do you think its worth the money to buy L glass on a t2i?