Here's another vote for Simple Green.
This morning I took a couple of plastic baggies and put in the deck pieces from Revell's 1/96 Cutty Sark which I'd painted with a flat black then, after curing for 24 hours, airbrushed a brown color (which I ended up not liking) over the black. I added Simple Green enough to make sure all painted surfaces were covered. I let it sit about an hour (much more and the Simple Green might eat through the baggie), took out the deck pieces and, with an old tootbrush, easily removed all but a minute amount of both layers of paint.
Since Simple Green is an eco-friendly, non-toxic cleaner, I much prefer using it to oven cleaner.
Mike