JJ1UK
I've no JP experience, but my spin comments are from PPRuNe (re the lost JP last weekend), from guys with RAF experience. Follow that thread - spin characteristics depend on type of JP they say, and some are nasty according to these guys who seem to know what bthey are talking about.
Also, putting a JP into a field is not the same as most GA types. Speed will be higher, the crew have almost no crash protection with no engine in front and very short nose.
SSD