I own one of these beasts.
In a buggy its excellent, very linear powerband with a wicked upper midrange and topend.

I used it in my truggy and it lacks the bottom end for a truggy. If you use it with a werks clutch and adjust for later engagement then it will work.
This is apparently JP's most powerfull engine. The internals are top notch. The casing inside has been worked, the crank is a work of art. The sleeve porting is beautifull.

I changed the sleeve with a P5 sleeve and must agree with razzor that the 5 port is a much better option. You can use any P5 sleeve and it will work in this engine. At least keep the option in mind. With the 5 port sleeve this engine uses more of its power. With the 8 port you get to 3/4 of the straight and it wants to only start delivering.