I daily my 1986 Audi 80 Sport and for the past half a year of uni life it has been absolutely brilliant. Performance that is more than adequate for modern days, well built, practical and mostly reliable. Plus it tends to get a lot of goodwill which is a benefit for sure. Parts supply is a big issue however, and I would be lying if I said the car was faultless. Occasionally there have been issues such as the throttle cable disconnecting and the alternator belt squealing, and rust is a constant worry. But, I feel safer driving it than I do the 480, although that is likely going to be my daily for the coming year due to insurance reasons.
The Audi has taken me to Denmark where I am currently, and was quite happy cruising at 90mph, even managed to hit 118mph on the Bahn, proving that you can use all of the speedometer on it. So yes, I do daily my classics and apart from having a fight when it comes to insurance, it is more than fine