Here is a better look at the 'die cast' Sonic Racers cars wave 1.
Diecast goes in little fake quotes there because they are ssssoooorttta diecast. A real model car enthusiast may complain! The only actual metal part of the car (that would be cast by the die) is the black area you see under there. It holds the axls for the wheels and gives it a bit of weight...but that's it. Usually the term diecast refers to the upper part of the car/the body outside that gives the car it's look, and that's where the discrepency is with these.
Their uppers are all plastic, and of course, so is the tiny figure in the drivers' seat. The cars are ok mini-likenesses of themselves, and the mini-figures are decent as well. With the back views you can see Tails' tails are well done, Sonic's head is shaped right & Eggman is fine/normal. They did a good job with the faces, (unlike some nkok) so if you de-box for play or display they'll do just fine.
The box-backs show that this is all of wave 1, and it was probably smart to have an 'enemy racer' on the first wave (instead of, say, Knuckles) so that kids can race them & root for Sonic & Tails to beat the Eggman one. They're bubble-carded so you can view most of it & it's easy to hang on the wall. You can collect Sonic Speed Star, Tails Whirlwind Sport & Eggman Egg Booster.