We tried some other local powdercoaters a while back that claimed to be able to do top-grade work for us. Well, lets just say our idea of top & their idea of top are 2 completely different levels
We decided to strip them & let our regular powdercoater (slower but better) do them. Here is what we found:
Sandblasting with the best cutting media takes forever.
We used a source in Ohio, called DECOATING, Inc. (419) 347-9191
Very good work, fast & not too expensive. They soak it in a liquid salt bath at high temps for hours, and it takes it right back to the sandblasted (or base) surface. They recommend blasting/cleaning it again to get a good adheasion the next time around.
Powdercoating is basically a plastic "type" material, and most any chemical eats it to some degree, just like painted surfaces.
It can also be wet-sanded like paint & buffed out or even repainted on top of the powdercoat. Just scuff the gloss off, get them clean & dry, and paint away with any paint safe on plastic stuff.
Hope that helps!