It really depends on what the weight of that plane will be.

I believe I saw a video with QQ with his 72" Yak and one of these motors.. while hovering was possible it was very apparent that it lacked power. He didnt really climb from a hover he more fell to the side and took off into KE or something less taxing on the engine.

If you are going to go the extra mile and put a pipe on it then great.. if not I would think twice about it.

Why a company advertises a power with a pipe on it is beyond me.. not everyone is going to put a pipe on it. They should put a stock muffler on it and let people judge real numbers knowing if they add a pipe it will increase.