Hi, Thinking about upgrading my camera my current camera is fuji s620 which as served me well with holiday/social shots. But now my girls have got really into Athletics of which i'm taking quite a few shots and i'm finding s620 quite limiting, so i'm looking for a good used SLR for taking fast moving sports shots. First recommendation i received was Canon 7D but at used £600 it was all my budget and without any lenses, then the next was 550d and spent what i'm saving on good lenses. Is the 550d better than a nikon d200 and then comes the question of which lens, i assume i'm better going with a cheaper body and a good quality lens. How much do i need to spend to get on a good quality lens and also which lens' should i be looking at. Thanks for any advice.