Just one guy's opinion, but I've used and own both.
If you're in a position where you need to remove your firearm on occasion - such as police officers who must remove sidearms and secure them in lockers before entering certain parts of court buildings; or even a lawfully armed civilian who wants to enter a commercial business with a "no firearms allowed" sign posted - then a paddle holster makes sense. It allows you to remove and replace your firearm/holster with the least inconvenience.
If you're NOT in that sort of position, however, get a belt holster. In my experience belt holsters do a better job of ensuring your firearm stays in the same location and position on your body, and that can be beneficial in a lot of ways - particularly if you're carrying concealed.
Each type of holster can be beneficial, it just depends which situation you'll be finding yourself that determines which one may work best for you.
Treat everyone you meet with dignity and respect....but have a plan to kill them just in case.