I drove our Fastrac home to Girard, Kansas from Stuttgart Arkansas when we bought it.  Load was going to be over height and over width to haul and it runs 47 miles per hour.  I left about 7 am and was at a meeting about 20 miles from home at 7 pm with one stop for a meal and another for a snack and break along the way. 

I really don't understand what all the 'wear and tear' is that many seem to be soo concerned about every time this issue is discussed here.  These machines routinely run for up to 24 hours straight under heavy loads when we are using them, running down the road is little more then idling in comparison.  Tire wear is really the only concern I see to be very valid, and I wouldn't worry too much about it.