Despite being a rather small update, the recent GTA Online DLC which added the Sultan and the Banshee to Benny's Original Motorworks has made quite a few waves. Initially plagued by a rather destructive bug and later heavily criticized by players due to the poor performance of the new vehicles, it seems that things have been figured out. The addition of the new vehicles to Benny's have started a few rumors about more cars being added over time, and that the Roosevelt from the leaked Valentine's Day DLC will also have customization features.

The Banshee 900R and Sultan RS, which are the upgraded versions of the stock cars, were categorized as "Super-Cars" and could allegedly compete with the likes of the Progen and Zentorno. In reality, the Banshee 900R was slower than the stock car, and the Sultan was nowhere near super either.
Then suddenly one day the Banshee 900R started winning races. It didn't take long for several players to report a performance upgrade and for others to confirm the change. Despite the tweak being rather apparent no official word about it came from Rockstar.