Hi all, I have a Canon Rebel XS. I was wondering if I should get a class 2 or class 4 or class 6 memory card. Is class 6 really that useful for my cam? or is class 4 is enough? Is Class 6 really good only for video cam where memory access is higher? I've been searching google on that, but I don't find anything about comparison for the class 2, 4 and 6... thank you for any help on that.