The likes of the Amd Fx 8120,8150,8320,8350 are middle ranking chips performance wise.
IMO they are decent chips.
They operate just below an i5 3570 etc. They are in no way comparable to the likes of the intel i7 3770 or i7 4770.
These chips perform at a whole different level to any of AMD offerings without comparing the more premium performance of the Intel i7 3820 etc
But for gaming the Intel is superior.
I own a Amd Fx 8150 and understand both it's strengths and weaknesses.
I also own other systems with Intel i7 860 and i5 330 CPU's.
Don't have hate for either platforms just use them for what I need them for.
But if you can use the AMD CPU's for your purpose they are adequate.