I have a Saito 1.20 in my CMP Hellcat, which is quite a bit smaller and lighter than the 109. It powers the Hellcat OK, but would be a bit weak in the 109. I would guess that it will fly scale, but you will have limited vertical and not much reserve power. On a good note the 109 is not tail heavy, so you could mount a 1.20 without huge amounts of nose weight.