Which one is better or what are the benefits on them?

Solution
No, you'd be surprised to know that RAM frequency does not matter much in gaming.
See this video link : http://www.youtube.com/watch?v=dWgzA2C61z4
In this video Linus Sebastian (most reputed techie on youtube) benchmarks and explains how even 2400 MHz RAM cannot show a noticeable difference in gaming FPS.
You're all right with 1600MHz RAM. No,need to buy a expensive one

Sbs95

Honorable
Dec 27, 2013
28
0
10,540


Cheers mate, though the 2133mhz isn't really more expensive, just a couple of bucks more.
And yeah, i've enjoyed watching Sebastians' videos, i've been searching up alot of things about pcs from utube and always hes face popped up. ^^