well the best car for the fastest laptimes is the F1 ofcourse, but for me the best car is more about how much fun it is to drive, so i give my oppinion from this perspective.
Best Cars for me:
-Tommy Kaira ZZ-ll (slightly modified Duck7892 setup, qualifying tires)
I love the handling on the ZZ-ll, it has a very predictable and different way of handling, the power comes out so sweet and its bloody fast with 900+ HP. When exiting corners, u really have to get the perfect line, open up the trottle very gentle(if not, u run wide instantly) and give more and more of those 900 horsepowers to the tarmac. When u do this the right way, u exit turns perfectly on the rumble-strips every time! Its got a lack of grip when braking so i use qualifying tires.
-Opel Astra Touring Car (My own Setup)
Its the perfect handling rear wheel driven car for me. PERFECT HANDLING, superb brakes and grip, not overpowered, the 811 hp is just right with the right gear ratios. And it holds his line perfectly, even when u brake from high speed into a slow corner when cornering already. VERY predictable and sweet car, ULTRA-stable at 300+ speeds. Almost too clean

. I will post my setup later.
-Suzuki GSX-R/4 (My own Setup)
I love the high revving engine sound, the sweet handling and the loads of grip! i actually ride it with hard tires and half downforce. very neutral riding and good for pushing on slower tracks like city di aria and cote d'azur. Deep forest rules with it aswell.
-Nissan R92CP (Duck7892 Setup)
Very nice handling supercar, Sweet ride. Bit too fast tho, so i only ride it when i really want sick speed 👍
-Renault Clio V6 24V (Duck7892 Setup)
Very nice "slow" car, good for pushing on slow tracks! really sweet handling and not at all frustrating to drive. Good for rookies who want to learn how to race!
This is only a small selection of my favorite cars ofcourse.