The benefits are not measured by fuel savings. They include the hassle free driving and constant self tuning functions. Improved drivability makes itself notable by a driver who pays attention to his engine.
Again, I'm a big proponent of EFI systems, but for a car that's driven once a week and is getting ready for one cross country trip, this is not necessarily the best investment for the OP. For a daily driver, absolutely. For a car that's only started once or twice a week to go for a cruise or take the missus out for ice cream, I could take it or leave it. These old cars were driven in stock configuration as daily drivers for many, mnay years, surely an unmodified engine can handle a cross country trip.
