Be sure to hop onto GTA V Online next week; you won't want to miss the 20 new Stunt Races headed your way.
The Special Vehicle Circuit, as the name implies, includes races tailored to specific Special Vehicles, so you're going to need to implement a whole mess of new tactics and skills. You'll be using the Rocket Voltic, Ruiner 2000, and Blazer Aqua (and you honestly can't go wrong with those) for anything from tunnel driving to parachuting.
To prepare for next week's release, there's also a bunch of new GTA Online bonuses kicking in this weekend through March 13 (on top of the ongoing things with Double GTA$ and RP Stunt Races). Aspiring kingpins can snag their own high-rise for 25% off Executive Offices and Office Garages before taking advantage of CEO bonuses for the whole weekend. Also, Warstock is slashing the SecuroServ prices on Special Vehicles, and Special Vehicle Missions will also dish out Double GTA$ & RP throughout the weekend. Bodyguards and Associates are also getting a Double GTA$ salary bump this weekend.
Finally, look out for the Progen GP1, which is going to be added to the supercar roster on Tuesday, March 14—the same day as the release of the Special Vehicle Circuit.