I've used a number of different decal papers and never noticed any real difference in thickness. I don't see that it really matters much as long as you printer handles the paper ok. This all gets discarded in the end. The key to the sealer is a couple thin, misted, applications so it doesn't run the ink. I have used the Testors product and never had problems but that was applies with a few mist coats anyway. Your specific printer's ink is a factor, so just keep what works.