I would always take the car that has been driven regularly over its life ... I've learned that lesson before the hard way. I had a lot of problems with a very low mileage 3.2 Carrera I bought years ago.

It's easy to freshen the interior on a car that's been driven, you can redye the seats, replace the mats, detail, and so forth, and have a 90k miles car look just as good as a 20k miles car, and the car will likely be in much better shape, especially if you are planning to drive it regularly.