Well, can't comment on the Zlin or the mini Spit but have flown and taught on both the Chippy (quite a lot) and on the real Spit. Chipmunk is great as a basic tailwheel trainer and will amply reward good handling procedures in and around the circuit but will let you know when you get it wrong. The relationship between pitch attitude (or alpha if you prefer) and approach speed is pretty linear and so when decelerating on finals the increase in nose up attitude to maintain a steady approach is predictable.
On the Spit the relationship is non-linear and so losing that last few knots of speed on finals requires a significant nose up attitude change and one feels very close to the stall however control is still perfectly adequate, it just feels uncomfortable. I've never seen it but I guess the Cl alpha curve is quite flat and goes non-linear quite early for the Spit wing.
Don't know if the mini Spit feels anything like that but if so then your man will need careful briefing. Can't offer much else but, if your man wants some dual on the real Spit come on down to Goodwood and we can oblige!
3 Ponit