Too Many Beseler Printmaker 35's

[GlassArt]

Does someone have any hints on determining which Beseler Printmaker 35's may be the best keepers without actually using them yet? I just acquired a bunch of Beseler Printmaker 35's from a school government auction...like 9 of them, along with a whole bunch of trays, timers and who knows what all.
I did B&W photography in High school on into college and have a lot of negatives in storage. The last was high contrast contact films of sandblasted glass then photo-etched onto etching printing plates. I printed from both the glass and the photo etch, used the glass in sculptures ending up with both 3D and 2D art presentations. a long while ago.
Anyway, I will probably hang onto one or two and a selection of the other stuff.