I try and avoid software that requires some sort of on line activation. I actually like my Steinberg USB elicencer. Once activated it has become the easiest software I own to move around and re install after a OS or OS drive upgrade. Sure it takes up a port, but it doesn't mind being on any port or hub. I can see it being a hassle on a laptop with 4 ports, but still a hub solves that issue. Just share with your wireless mouse etc.
The old two number system was my favorite style but it was not the best for them for piracy.
The new system allows them to track how many installs your using. It was said that they would not be worrying about this in general, but if one registration all of a sudden has more than a dozen activation's they would be able to investigate possible piracy or say a studio cheating on user count.