I flew one of these for an hour back in the early 80s, in the Netherlands. From what I remember, it's smooth, performs well and has no vices. It's also aerobatic (though not, I suspect, with 4 up). I seem to recall that we did stalls and spins 2 up and that everything was perfectly conventional.
And it's different in looks to the PiperCessnas that abound, but will have a standard engine that any licenced engineer can maintain easily enough.
The only bad news I have heard about them was when a group who operated one at Barton had a lot of corrosion problems and essentially had to get the thing rebuilt. It's no longer at Barton now - I wonder if it's "your" machine?
May be worth checking to see if there is any history of corrosion with this one, also whether its been kept outside (as was the Barton one) or inside.
Might be worth checking around to see if there's an owners/users club - may be good in terms of assessing airframe spares availability.............