Once a week or so. If i ever have a car in the shop i'll drive it until it's fixed. (This is based on the amount that I drive my 68 falcon currently) In the last year i think i've put maybe 1000 miles on the falcon. It doesn't have air though so during the summer i'm less inclined to drive it. The truck however is much more safe and comfortable so i may drive it a little more.
Currently the truck (most all of it including the Engine, suspension, tires, wheels, tranny) are all brand new and have less than 80 miles on them.