Hard drive speed

[aaranu]

Hello, I currently have a 2tb WD green HDD (5400rpm @ 6gb/s)

Ive been playing most of the new realease games, homefront, crysis 2 etc... But what ive been wondering how much better would say the WD black be (7200rpm @ 6gb/s)
ive done some research my self and ive found that most of the time you will never reach that 6gb/s point, but just how much better would the black be?

thanks

 

[aaranu]

Sorry i mean 5400 @ 3gb/s