Changing Alternator regulators

For christmas my dad is having my externally regulated alternator changed to a internally one, the guy at the alternator shop is putting a regulator on my alternator, making it a 1 wire hookup. Has anyone heard of this, is there any pros and cons, it is only $35 because dad went to school with the owner. My alternator is also a 100amp. I just want to know if it is a reliable way for my EFI conversion since EFI doesnt like externally regulated ones.
 
i got the alternator today it is a now a 1 wire hookup with a regulator on the back everything is now on the alternator it is pretty neat i dont see it causing any problems with the EFI does anyone else, since everything is now contained in the alternator.