Well I've got a 500 and I'm very pleased with it. The 3x optical is very useful and the 12x digital zoom isn't as bad as you'd think.

I can imagine getting chromatic abberations with a lense like that, but really I suppose you need to go to somewhere like Jessops to have a go and see what the pictures look like.

The 60FPS movie capture mode is probably the only thing that would make me want a 700 over a 500.