Fun, but not addicting
The introduction of Nitrous is a change; it greatly boosts your car speed for a limited amount of time. You want to use it at the right moment, because to recharge it, you need to negotiate ridges dextrously for several times until the meter fills up. When used correctly, your position can easily jump a few steps up in just a few seconds (eg. 3rd to 1st).
The music available in the background is diverse; you have many options to choose from. However, the effect does wear off after a while. Anyway, the focus is on the race, not the music. So, the music is not so essential after all.
I have tried other racing games like Wipeout Pulse, to name but one. I find that Ridge Racer is a good game, but not an exceptional one. It is fun, but not addicting to put it succinctly.