Knife or Extreme 330?
Have never seen the Goldberg, but I did fly my Knife kit for several years - it flew just fine with the MVVS 40. It finally got so beat up I had to retire the fuselage, but I still have the wing and tail.
I am now flying the Knife ARF with the MVVS 49 in it. It is slightly heavier than the kit version. - If you get it tail heavy enough, it is one awesome machine. I especially like the way you can land it on the tailwheel only and drag it a way on the tailwheel only.
Bob T.