I crewed on one for a race weekend in the UK a couple years ago (although it would have been a newer model than a 79). They are often compared to Bennetau and Jeunnau and thought of favorably by European sailors for a boat in that price class. I got some helm time and found it to be incredibly responsive and pointed very well. It was a very comfortable boat to spend a long weekend on, too. Other than that, I'd have to leave more detailed comments to those that may know more about the rep of the 79. Good luck.
S/V Don't Panic!
“Navigare necesse est, vivere non est necesse” To Sail is vital, to live is not.