Having tried 90% of the Magpul stocks as well as B5 systems, BCM gunfighter, MFT Tac, VLTOR and a few other military stocks I'll simply say this; in a game where the guns have either zero or almost zero recoil, none of it really matters.
Pick something that's a good fit on the buffer tube. If you really must have storage in the stock or sling attachment points then choose accordingly but I personally recommend only attaching slings direct to the gun and keeping the stock nice and light. If you want battery storage in there look at the krytac stock or PTS EPS.