I like 20 round Lancer and P-mags better than 30 rounders for most things.
@ 20's are short so makes it nice to shoot off the bench, in or from a SXS, truck hood, truck bed, car roof & back window, ATV, deer blind, big boulders etc.
Easy to stuff in back pocket. I have some but I don't like metal mags, & Have fun.

I would have got him too but a Dad Blam snow flake hit me in da eye....