I would think that the surplus of the variations of them, the fact that they bolt up to a plethora of transmission options, and you can make the computer in them do whatever it is you want without have to be a computer programmer to break the encryption, all add to the use as well as the size/packaging.
I personally like the 5.0 as well, throw some Borla mufflers on one and it makes a rumble that is darn near perfect.