m16's jam alot and the 5.56 round is horrible for stopping power. m4 is more reliable and easier to use is close quarters but still uses the 5.56. ak47 jams less often (expecially the soviet ak), simpler/more reliable, and uses the 7.62 which actually has stopping power.
i've never had mine jam up, not even once. but i do keep it clean. i would have to agree on you with the 5.56 not being the best round for stopping power though, but its just my personal choice out of what i have that i would grab if i could only grab 1.
