I don't know about the pricing, but there are few things you need to be aware of:
1) It draws more power, if you have other electrical item above and beyond stock i.e. electric fuel pump, cool amplifier, and if the battery is in the trunk as some cars have that mosification make sure you have a proper alternator to handle the extra load.
2) You may get some extra horses out of the engine, the claims are usually quite large compared to reality especially when your talking net increase at the wheels.
3) They kind of look cool
I for one though have never really seen that it's must have item, the old mechanical set up has NEVER let me down.
Bain
