My OMP Edge profile (.40 size) climbs inverted when the tank is full and will do an outside loop when the tank is near empty.

It is very stable upright, even with the tank near empty, but it IS hard to fly inverted. The up elevator input to keep it level is very counter-intuitive and awkward.

The scary thing is that on the first flight it was far more tail heavy. Since then, I have moved the engine forward an inch and added a heavier spinner.

Leonard