RE: ARFs?
RC Redneck- I have flown the 80" 540 with a BME 44. It is great. 3D flying was awsome. Hovering was about 1/3rd throttle and flyout was super. That was the airplane that got me hooked on the big profiles. I have built 3 of them and all are fantastic flyers.
The first had a DA 50, then a OS Twin four-stroke. ( my own )
Be careful in mounting the BME. It does vibrate more than say, a DA 50 or 3W 50.
Try to mount the engineas far back on the mounts as you can, as it will help to absorb the vibration. Balance should not be a problem. If you check the battery hatch modification I did on the MOAP, you can build the CG adjustment into the plane. It is real easy to change CG in a few minutes with that setup.
Hope this helps. Good luck and HAVE FUN!!
Vic M. of AZ