This set is, I believe, a misnomer. Super cars, such as the Ferrari Enzo, Lamborghini Aventador, and Mercedes CLK all have their engines mid-mount (or what I call rear-mount, as it's behind the passenger area). This car is more of a sports car, or, if you really want to get technical, a Chevy Corvette. Sports cars, such as the Chevy Corvette, Ferrari California, Dodge Viper, and BMW Z4 all have front-mount engines. There are exceptions to this, since Porches have rear-mounts and the more common ones are sports cars.
The cost averaging I've figured out is that 1 brick is anywhere from five cents to a dime in US dollars. Now, some bricks cost even less (I think the lowest is three cents) and some are more (the NXT CPU is about $100, since it's a computer processor), but a minimum of 100 bricks is about $10 in the US.
The reason I said Playability was a 3 was because it's more of a display model.