Well, if in car mode it was unpleasant to drive and could only do five miles to the gallon, and in plane mode it was unpleasant to fly and could only do a few miles on a full tank, then I probably wouldn't want one, no.
Though it would look cool in the driveway, that's where it would probably stay.
Actually there were a few attempts at it in the 60s. The Boeing museum in Seattle has one
Errr. I'm not helping am I?