Yes, unfortunately it takes 45mins to get to the airport for me, then another 15 mins to pre-flight, 15 minutes of runup, warming engines, taxiing etc. So now you're already 1hr 15mins behind if you'd left in the car. Same at the other end. 2-2,5hrs. So for short distances, it's not at all time effective. For longer distances, but not too long, then it starts to kind of make sense. Too long and airline travel makes more sense time wise. Sweet spot is probably somewhere between 250-600nm as a guess. Can be expanded slightly if one considers two points with bad transportation links or you have a fast aircraft.