Yeah, those things were the bees knees back then... Pretty rare now, and a bit of an oddity: the helicopter kit was something like 700 Euro, the engine 1200 or more and it was near impossible to fit that mechanics in a fuselage due to the double exhaust (which alone was a set, close to 400 Euro).
The SkyFox was a trainer of modular design, intended to first use as a trainer, then after sufficient skills transfer the mechanics to any of the about 30 different fuselages availlable for it. None of the fuselage kits were really suitable for the BoxerFox, and the Boxerfox did not really like being "fuselaged" due to cooling issues anyway.

So it has always remained a rare bird...

It was also butt-ugly! Here's one in flight:

Looking at the smoke trails I believe he is burning up his portside cylinder...