I play mostly with a pair of DT990 Pro headphones which I use for my job as well, and to me the audio sounds pretty good it's a bit quiet in general volume the only sounds I struggle to hear most or that are most in the back of the enviroment mix are character noises, footsteps when walking and load noises (clothes rustling,etc) so it's mostly just ambient noises. The dynamic range could do with abit more work as well a greater difference between the firing of a rifle and the explosion of a grenade or shell would be more noticiable and fitting with it.
On the whole sound system, it really doesn't matter what you've got if it's a good system as it's all subjective the HS50M's are a cracking pair of studio mixing monitors but to others they may not sound so good for games (or music though i disagree on that one).