I did a full review with photos here:
http://www.eurobricks.com/forum/index.php?showtopic=27188&hl=

(B4 saying this wasn't helpful, at least read the full review first)

Here is the closing of that review:

Features
With so many cars, they only gave you a few aftermarket pieces to modify them. But the set does work well. Store doors that open. Hey. If you think about it, the human that would fit the height of the door would be too tall to fit into the cars. They do give alot of tires. Speaking of tires, this set has at least three different sizes. The classic car, has skinny front tires and large slicks for the rear. And the rest of the cars all have low profile tires. Some tires have writing on them, but yet, some don't.

Issues
Besides having this scale be a bit off, meaning its not for minifigs, it would seem the stores are made for the minifigs or larger. Yet none of the cars could fit one. Also, while all the cars are to scale, they would be a little "off" scale when you have them lined up. Example would be that the Truck should be bigger, yet it has the same size tires as the cars. And some of the sport cars doesn't look like it could fit the same person that would fit into the truck. But if you squint... all looks fine and very much playable.
Only other thing that bothered me was, for a set that required heavly on the stickers to give a realistic feel, they should've found a way to pack it into the box so it wouldn't get damaged.

My rating:

Playability: 4 out of 5. It's cars. You push it, it rolls. And they give you enough stores to work your imagination.
Design: 3 out of 5. Everybody who saw the cars thought they were neat. But the scale just didn't always match.
Build experience: 2 out of 5. Everything was easy to put together. But get someone to help you with the stickers if you're bad at putting them on.
Overall: 3.5 of 5. Buy it if you like the series. Price per pieces are good. Now, you can get a set for about $70. That's less than the "normal" .10cents a piece by a lot.