I love my K2s.. I think the model I have is called Exotech.. they're kind of expensive, but they are sweet!
I think I got them from overstock for about 40% off regular price.. so like $150, if I remember correctly.  That was a few years ago.
look for aluminum chassis with some sort of impact absorption, ABEC5 or better bearings and the ability to put  80mm wheels or larger on them.  K2 are great skates!