The intended use is to be able to stage planes closer together in busy airspace. So if your flying into New York, ATC will be able to have the arriving planes closer together. Instead of radar, it will be gps information.

The main reason I’ll need it, is it is required if I want to fly higher than 3000’ over the Gulf. If I want to fly down to Key West I would either have to overfly the islands or low. It is much safer to fly high within gliding distance of land. And it would be very inconvenient having to stay 30 miles outside of the larger city’s.