Oh I remember having trouble grabbing magazines when I started playing. It was very frustrating. I think I tweaked some settings and/or got really used to it, because I was playing fine later.
I really, really disliked aiming long weapons and I basically gave up using their scopes. Went all in with smallers and faster weapons. I don't remember it being wobbly and maybe that's because I never insisted in using this kind of gun. But since the resolution such and could be higher, maybe that's the cause of the wobbling.