I just recently bought a 50's Dewalt GA as well. Sadly, I just realized last night as I went to adjust it that it has fairly similar wear to Larry's... There's a little bit of side-to-side play in carriage/motor assembly, and it's coming from the bearings in the arm. There's play for the first half of the stroke, but no play toward teh end of the arm... which can only mean wear to the machined ways. I can't feel any variation or steps in the ways with my fingers, so it's pretty subtle. But I really really wish I had caught this issue before I bought the machine.
I was able to adjust the bearings such that the play is almost imperceptible, but I can still hear it when I hold my ear to the arm and wiggle the motor. I'm hopeful that further adjustment will resolve it, but the only way to remove the slop for the first half of the travel is to make it pretty tight for the last half of the travel. Fingers crossed, because I was really looking forward to having this machine, and I just dropped $500 on it.
So, to the OP, while I'm sure it's true that these saws are really accurate assuming they aren't worn, I strongly recommend doing your due diligence before buying one. Inspect the heck out of the ways, making sure there is no play whatsoever... or if there is play, make sure it's consistent along the full travel of the motor.