Mate - you would be surprised at how good it works. It creates the thickest, whitest smoke ever. Only problem, it does leave a greasy residue and kills the grass. I don't know what long term effects it will have on their planes - one of them is composite.

Jburry - thanks for the info on the crankcase. Yes, it does have a crankcase bearing and shaft on the front and back so I will look at tapping somewhere where it wont compromise the case. I'm not sure what you don't quite get, but as i see it the cost is absolutly minimal, no additional battery or pump weight, good thick smoke (cheap too) and reliability over the more traditional pump type systems. I don't have warranty issues with the engine - there was never any (ebay). I guess the worst that can happen is it wont work.