I agree with Beags but given I flew the JP 5A as a student and then again later instructing and then again again instructing instructing I may be biased...
Side by side seating - great for watching Blogg's head/eyes through a Stall turn.. No nasty vices for the basic stuff..Straight and Level One, Straight and Level Two, Straight and Level ..I'm bored now but it would dependably do all the Power+attitude+Trim stuff until the cows came home.
Then move forward umpteen hours on the course and the same aircraft could blast around at low level at (?) 240 IAS with enough fuel to do so for a decent low level navex but also not quite enough to mean Bloggs could ignore the fuel gauges.
Good (by 60's/70's ergonomic slum standards) instrument fit, including raw ILS.
A good spinner - no vices with incipient spinning - for full spinning- usually no probs if you played it straight with a basic Bloggs (though I did see one high rotational..it did , as per the pilot's notes straighten out OK eventually
) ..OTOH it could deliberately be made into a very entertaining spinner ( as in oscillatory - "that thump you hear is your helmet hitting the canopy" ) if you wanted it to be so for the benefit of the big boys/fast jet customers we used to spin for famil purpose at CFS.
I thought it was a really good solid fundamentally honest basic jet training platform...
If you want some gripes..Not great in icing (icing let-downs ring a bell?) - a bit of an issue in the UK winter but then again what basic trainer is ? The mighty JP3 was a better aeros machine at low altitude - lighter aileron forces and the tip tanks gave a better reference in the vertical...and the land away personal kit stowage - a tin container about the size of two shoe boxes) was dire...