I've had 2 different engines in mine and the only deadsticks I've had were my own fault or a couple recent ones that appear to have been caused by bad fuel.
It seems you have no regards for tank positioning , which is fine, but how can you be convinced that all three of your planes problems wasn't from tank position vs bad fuel ? Of course a new bottle of fuel has more nitro potency so it may only seem that this solved the problem, but did it really ?
I read in RCU almost one hundred times a guy posting about an engine that would not run , and some one replying , lower the tank. I have NEVER seen you, Chuck, respond it has nothing to do with the tank position.
My point is simple , the tank position can't be lowered on this plane , thus far the positioning of the engine is a mistake.