We do them, very rarely, without any real heat. We have a primer we spray on them, send them down the dryer, then use air-dry multi-purpose inks. A few extra steps, but absolutely no curling up. We send them through the dryer quickly at 250 or so, gas only, IR panels off. This gives us the best results, and we charge what we need to. If they want cheap, cheap, cheap, then we'll send it to an ASI distributor.
Steve