I've been checking for UV variations for years, since many are given separate CG numbers.

One problems I have encountered is that the UV printing is fairly easy to remove by cleaning. Sometimes even a lightly worn chip will have all, or almost all, of its UV mark removed. It is also fairly easy to add a simple UV logo, such as the H&C, with UV ink. I did it (just to see if it could be done) with the ink from a child's "spy kit".

Something to keep in mind if there is a big difference in price between a UV and non-UV marked chip.