It allows the removal of the Air Flow Meters which is particularly advantageous for large turbo applications such as the TRUST T88, HKS T517Z or twin GT3540's etc.... drag setups.
I've heard it also uses an ignition cut for the rev limiter instead of a fuel cut (which the STD Power FC uses) but I'm not sure if that's true or not.
If you want a Power FC for a road car I don't think it's overly necessary unless your idea of a road car to strap the biggest turbo on you can think of. For most people who don't upgrade the turbo or only upgrade slightly to keep good engine response and minimal lag, the STD Power FC will be sufficient.