Just finished painting the cockpit three days ago... with guess what.. el chepo Harbor Freight gun, not an HVLP, just a plain old gun. Result, one run, no drips, no problem. The run buffed out in about 20 minutes with 600, 1500 and then rubbing coumpound. We used PPG Omni paint (PPG's cheap line auto paint, exterior will be better stuff).
Used very low pressure for a standard gun, Omni is extremely thin stuff. Be prepared, when spraying in a box (cockpit) with this method the overspray is overwelming!
I'm sure there are better guns, but that's what we used.
Larry