Originally Posted by FBinNY

In my almost 50 years of experience, I have never run into a rim that was defective because it as out of round, or otherwise bent, except for a few that were very obviously bent in transit. BITD we had to worry about local issues at the joint, but even that was considered relatively normal, and the builders problem.

These days rims are made to tighter standards than in the past and I wouldn't be overly concerned about non obvious damage. General ovalness or potato chip shape come out in the build, so you need only look for local changes in curvature (flat spots that might happen in transit, usually to the end rims in a bunch) which will be hard to correct.

For a quick inspection, roll the rims on a wooden floor and listen for defects which will show up as a sudden change in rolling sound. Also eyeball the rims for issues with eyelets. I you're really concerned, make a wooden template that covers 1/4 or so of a rim's arc, and check suspicious areas, especially joints against it.