I have had one of these for about a month now and flew it for the first time 12/30.I used an OS 160 4-stroke twin that I had picked up some time ago that needed a home, and this was the perfect plane for it.It fits in the cowl without any cut-outs other than cooling air exit at the bottom and a small hole for the needle valve adjustment.With this engine it flies in a very scale-like manner and will do any aerobatics the full size plane will do with power to spare,plus the sound of that twin is very cool,especially on a low and slow pass over the runway.The quality of this ARF is one of the best I have seen and I made very few changes other than the tail-wheel and a couple pieces of hardware.I also used two elevator servos and modified the landing gear support rods using coil springs and heat-shrink tubing for bungees.All of the changes I made were pretty much personal preferences and I'm sure the plane would perform just fine with the stock hardware.