I was actually hoping to get away from the cheapo compressors because of the noise they make, even with a pair of ear defenders on it's a bit loud lol. Had thought about running 2 machines together & haven't entirely written the idea off but I'm not in a huge rush to get it going at the moment. Will kind of manage to do my wheels with it even if it does take a lot longer than it should & glass etching will probably need a lot less pressure although I haven't really researched that at the moment.
Pity I don't have a 3 phase supply in the unit as you seem to be able to pick up used screw compressors at a reasonable price although I haven't looked at the running costs of them.