If I was that worried about it, I'd just ad a few ounces of oil to my fuel. As long as the engine isn't losing its compression, I don't think it's hurting anything. Sure hovering out a whole tank is harder on an engine than flying around, but it's not like you have a house payment tied up in the Pro 46. Play hard and die young.
You know what's coming next.
Also..couldn't you get about 2 Pro 46's for the price of 1 OS 46 Heli engine?? And the heli engine will weigh more...just sayin'.