GDL-0010. I don't think I can afford to replace it.
I don't know that it's bad yet, but it does have scratches and it worries me. I have had it for 10 weeks now and never have been able to use it. My DIMM turned out to be DOA, and I'm waiting for another one to arrive.
Maybe you can take the disc somewhere and have it professionally resurfaced? Any resurfacing fee would be a drop in the bucket compared to the game's market value.
PS- Don't use any of those cheap hand-held "resurfacers" (Disc Doctor and such). In my experience, using them causes discs to go from some errors to disc completely unreadable. Have a company do it, like Game Crazy or something.