Put me down as a 77/79 fan, too. We drove that route to FL last March, and loved it. Beautiful scenery, nice welcome centers, convenient gas, etc. On the way back, we did hit one of those infamous mountain snowstorms with almost 0 visibility, but DH just followed behind a nice truck which seemed stable, and probably knew the route well, and made a nifty trail blazer, until we got through it.
In April, we did the I-75 to my SIL's in Tennessee and hated it. The scenery through Detroit just seemed so bleak (although maybe we were just spoiled?), compared to the other route, and traffic through/around Cincinnati seemed conjured by Hades himself.
Anyway, we decided then that we'd been doing it wrong: we should always fly to visit my SIL, and drive to WDW.
Kungaloosh!
Morticia.