corsair CX series power supplies are not so great either ,
but still much better than aerocool junk ...
in comparison:
good power supplies are able to deliver their rated power and stay stable ,
even under heavy load ,
they are more efficient and have much lower ripple levels
and tighter voltage regulation on the rails ...
due to higher efficiency less heat is generated inside the good power supplies ,
they also have better quality capacitors and fans inside them ,
that means longer lifespan ...
read websites like jonnyguru , hardocp and hardwaresecrets for more information ...