I did a UDS for a co-worker that had a tan liner (it contained high fructose corn syrup). After two good burns, it wasn't too hard to remove the liner with a random orbit sander using 40 grit. It wasn't fun, mind you, but wasn't horrible either, just wear a mask! I think I ran a total of 5 pallets and a few oak logs in it. The liner just laughs at JASCO paint remover, don't waste your time or remover.