Second hand record turntable - Which one?

You’d be fortunate to find someone competent and honest enough to do all the testing that Bill recommends, and if this rare individual is in the audio business, the cost of those services is likely to double or more than double the base cost of the units you listed. So it’s good that the Rega is not a very old unit, and I say again, buy from a seller who will guarantee the condition. If there are gross problems, you’ll soon know.

The way I think of it, there are two reasons to buy a used TT. One is to save money over the cost of a new sample of the TT you seek, and the other is because the TT you most want to own is no longer in production. The TTs you list are inexpensive, but you don't say how much you would be willing to spend on a new TT. If $350 or less does represent your "budget", then I would recommend you purchase something used, because there is not much to be found in the way of new TTs that would exceed or even equal the ones you list in performance. I say this although I am not myself a big fan of either Rega or Pro-ject. If you buy used, best to buy from a dealer or some other seller who is willing to guarantee the working condition of the TT. That warranty should be a major determinant.