O-Pee-Chee if you're talking about high grade or raw gradable copies. The printing QC for OPC was terrible as was the printing stock. There are tons of diamond cuts, miscuts, and rough edges. The printing for Tiffany was much better as a whole even with the lower print runs than even OPC.
I had that Mudcats Glossy set for a while too. I moved it on to @Therion because he needed the Darryl Kile in it. Glad you managed to snag one.
The production numbers are shaky at best. There are allegedly 500 of the 1989 Star Glassy Gastonia Rangers sets (personal memory and Beckett lists them...
All the glossy sets I've seen have either been a totally different color, a la the Alomars, or a the same color scheme but a different design like the 1989 Star Glossy minor league sets.