Uh, that's quite the range of prices on interfaces? You've got a $100 M-Audio box, a $400 Presonus box and then an $800 Focusrite box.
Is that really your spending range? I don't even know why you'd be looking at the $100 M-Audio stuff if you can afford the Focusrite. Of the three that's head and shoulders the best sounding unit.
But there's plenty of competition in the $800-interface space to check out. MoTU for certain. You might even be able to find an older, used RME unit -- or even one of their new, smaller ones.