I object to Auto-Shotguns. There is an auto shotgun out there with less recoil than a 12 gauge. Ive seen small women fire it in short bursts from the HIP and they barley raise their arms.
That's because they loaded birdshot. The gun is not responsible for recoil, the cartridge is.
M4A1. The "armalite"(M4/M16/AR15) family is an overall better choice over any Kalashnikov gun. The M4 has better modularity, is more ergonomic, looks better, and is just an overall better weapon to work with besides the maitence but, Pmags and good treatment make that less of an issue.
The armalite platform is a true and tried design that works, if it didn't so many guns wouldn't still be using the same design.
Soldiers complain about dust jamming their weapons all the time, it is definitely a much poorer choice of weapon. If you want a quick comparison, Deadliest Warrior IRA Vs. Taliban episode compares the AR-15 and the AK-47. Not so many guns actually use the same design, any Stoner design is a colt M16/M4 model (which there are only a few different types of each gun). Even the ironsights on the AR-15 platform are absolute garbage. While the M4 does excel in being modular, I'd still say the Kalashnikov design is far superior. If anything, I'd argue that the Stoner platform is better for urban environments than engagements in harsh environments like the desert, jungle, or mountains. The Kalashnikov platform is well-equipped to suit any environment, be it urban or natural (Shortened "u" variants are extremely compact and therefore excel in CQC situations and the design is the same and therefore reliable).
Even more so, the AK design is much more simple than the AR design, making it easier to strip and repair on the field, and even easier to train conscripts, which is one reason it's used by guerrilla armies all over the world.
As for ergonomics, disagree again, after holding 2 AR-15's and 3 different types of AK model, I can safely say that the wooden solid stock is much more comfortable than the AR's synthetic stock, same with the grip (the synthetic grip on my airsoft AKM is also more comfortable than AR variant grips),
but obviously this is just my opinion.