So who is the go-to shop for full custom 'tactical' M&P these days? I feel like there are a zillion shops that do Glocks and Sig 320s (although that is sure to change), but hardly any for M&Ps.
If you want one modified, Floyd's Custom Shop gets mentioned the most from what I see. Jagerwerks gets mentioned more for other brands, but also work on M&Ps.
If you want something turn-key, there are the Ed Brown Fueled Series, but you certainly pay dearly for them.