It's been discussed numerous times in numerous forums, but a very short summary is that it isn't just any old Honda reg/rec, but it's the MOSFET ones which are an improved item.
These use a different semiconductor (MOSFET) to do the business, they generally have less internal heat genration due to the technology and deliver a more stable output. The technical details are available elsewhere in great depth. They still work on a shunt principle though.
They are generally rather bigger physically than the std SV item and connections are different so some mods are required to fit one. They are often referred to as a "Shindengen" type, see
Shindengen site .
I think a lot of folk have had useful help/parts from
Eastern Beaver
They come in various forms, recognisable by an "FH" reference (FH008, FH010 etc) but with different physical appearance. As far as I know they generally have a double socket arrangement (3 phase versions), I've fitted 2 to a couple of my bikes, one came from a Honda ATV and one from a Kawasaki ZX10. I didn't get the correct plugs, though that would make a much more professional installation, I simply got the blade connectors out of the stock plug and fitted separate plastic blade covers.
The 3 alternator wires can go on any of the 3 inputs, just make sure you get the pos and neg output wires on the correct pins. AFAIK the pos/neg is always in the same arrangement as shown in the Eastern Beaver site pics (pos is the inboard pin), but always double check.