What's the best Saab ever made?
I think the answer is that there isn't one specific model.
I've had three classic 900 3 door hatchbacks and currently have a 1999 9-3 and 2005 9-3 (9-3SS). The 1999 was bought used and with high mileage so it might not be a good car for comparison. Every Saab that I've had had pluses and minuses.
As far as driving fast and negotiating a curve, the 9-3SS is the best. In terms of practicality, I think the classic 900 was the best, particularly the latest 900 that I had, a 1990.
I haven't even thought it through carefully. Maybe some deep thought, a comparison chart, etc.