I've got 7's on my bike (see the For Sale Post on my bike - blatant advertising I know
) and they've been a great wheel. They are on the noisier side, but for me they've been a good solid wheel.
Building a set up can be cheaper, but depends where you source the components from. Also if you've got the patience.....
I have a set of American Classic rims (purchased off Fleabay) laced to Novatec Hubs. I know the hubs aren't the greatest, but I used them to keep the cost down. Having said that I haven't had an issue with them at all.
Sometimes Cell have specials on wheelsets like Easton's.