I don\'t care for any of the Ridge Racer Series.
GT 1 & 2 have hundreds of cars to choose from. In addition the upgrades are not "Stage 1", "Stage 2", etc.
GT upgrades are in the form of actual engine mechanics like, flywheels, tires, turbo kits.
Plus there are hundreds more tracks and the driving mechanics are much more precise, IMO.
The graphics may not be as good as Ridge Racer, but gameplay beats it hands down.
I like GT better personally.