Yes, that site you posted had links to all three types of cars. The rundown is as follows:
MiniZ -- Most sophisticated of the bunch. About 1/24 scale, approx 6 inches long, RWD, lots of mods available. ~$130 shipped
MiniX -- Same as MiniZ, but with AWD and not as many mods. ~$150 shipped
Indoor Racer -- About 4.5 inches long, 1/43 scale, not many mods, but they are very fun and pretty quick little buggers! ~90 shipped
Bit Char-G -- Not to scale, about 2.5 inches long. Not as modifiable, but look like they are fun as hell. I am getting one of these to mess around with. ~$30 shipped
Bit Char-A -- The newer version of the Char-G, with a larger motor and batteries. ~$40 shipped
Each one of these cars has a remote and charger associated with it. The Char-G cars come in a case where the base is the charger and the controller. All have interchangable AM crystals so you can race many cars at once. Most of these are Japanese or Chinese made, there are some knock-offs that sell cheaper, but I have read that the quality is lacking.
My friend Mike and I would love to make more parts and bodies for any of these models. So whichever seems to be the most popular woudl be the one we concentrate on. To me, the MiniZ and MiniX cars are a bit too big and pricey. The Indoor Racers look very detailed and offer a good about of fun for less than 100 bucks. The Bit Char-G cars are goofy looking, but cheap and incredibly small!