Common bees are a better bet. Rocky lack fertility, so with those you're more likely to simply run out of bees.
No.... Because rockies are hive bees, so you'd not need to breed them. Commons require breeding, although a tiny amount of it.And why are they easier to get...? Because they don't have minimal fertility.
http://mc.nessirojgaming.eu/bees/index.php?title=LifespanIm trying to get this trait so I can get a serum with it.