I bought 3 B USA Bristol M1's many years ago. Dad and I sat down and built all 3 at the same time. 1 was powered with a Magnum 52, mine was powered with an OS 70, and dads had an old OS 90. All 4 strokes.
They all flew great, regardless of engine sizes. I let one of my instructors fly my M1. He poured the coals to it, and it hooked hard right and flipped over in the grass. He was embarrassed about it, and asked if I had seen it. Yup!! Sure did! I said, ease the power into it, and just let it do its thing.