I don't really know how to evaluate the ways
Hey Casey,
I consider getting my first small lathe (Craftsman/Atlas 109) a great experience, not so much because it worked so well, but because it was a fairly cheap lesson in how to better evaluate a lathe.
As posted here:
http://www.mermac.com/advicenew.html
For me I now consider the number one test for wear on the ways is:
1) put the carriage near the headstock (where most of the wear happens)
2) tighten the carriage lock so you can just still move it with the hand-wheel without too much force
3) move the carriage towards the tail-stock and see when/if resistance is felt
you can then play with the carriage hand-wheel and lock to "read" the length of the ways.
This gives a great feel for the wear on the ways when you're "in the field" with no tools.
I am not saying not to buy a lathe with some slop, just to use that as an quick gauge of what your looking at.
Much of it depends on your expectations, know your parts application and your machine.
If I'm working on a regular automotive part or hand tool, then being out 10-20 thou (or more!) might be fine, if it's a bushing or requires close fit I want better.......I _never_ make parts for NASA.
The more you know about your machine the better you can plan to work-around any short comings, and get the accuracy you need for that project.
also see here for much good advice:
http://www.hobby-machinist.com/threads/how-to-select-and-buy-a-metalworking-lathe.25974/
-brino