I've personally ran a few two-strokes inverted. no problems - if you set up the tank correctly. Just make sure the tank is not tooooo high and you'll have no problems. Some current ARFs show mounting two-cycle engines inverted (GP Venus, Flip 3d, etc, etc).

It will run fine inverted and should be just fine without on-board glow.

The engines I've run inverted are OS 50SX and ST 51.