So far I have gathered that

M416 has low recoil in the game. Weak 4 hit kill.

MP7 MOD has really low spread. Really low damage.

I am going to get one of these permanent. I have considered getting the MP7 MOD but still not sure.

I am going to be playing lots of grave digger, sector 25 and death room.

So which weapon is better considering the maps listed above?