I'd rather have an M&P .22 MAGNUM than a 5.7. It comes with a 30 round mag instead of 22, and although it's not cheap, .22 WMR is still a LOT cheaper than 5.7x28mm. Like $900 cheaper for 2,0000 rounds at ammo .com, the first place I looked. $500 vs. $1,400, or 2.8 times the price for 5.7mm. The pistol lists for $50 less too, but the cost of ammo is more important to me. It barks like a centerfire but kicks like a .22 LR.