Looking to buy an Engine for this beast and cannot decide. Bruce specifies to NOT overpower this fine craft. I was planning on going with a Saito 80, but it is not on sale. The Saito 72 and 91 are though. So, which would better suit this plane?

I am not nto overpowering. I put a Saito 100 on my Ultra Stick 60 and have not had it over 1/2 throttle yet because it is WAY too fast for me.