What's the deal with S&W M&P AR serial numbers?

[Dragline]

I thought I remembered reading a while back about an issue with the M&P AR's and try not to get a low serial number or something to that effect.

Can someone here kindly fill me in on the details?

Also, how are the M&P AR's being regarded lately? What's the general consenses?

Thanks...

[Usingmyrights]

As far as I can tell its the 50K through upper 50k area

[the iceman]

Mine is in the 63k area and it functions flawlessly.

[centennial]

The early SW M&P rifles were essentially Stags with a different roll mark.
SW then switched to other vendors for parts and had problems with out of spec mag wells.
All is good with them now. They are a pretty good value.
If you get one with an out of spec mag well, a file will cure the problem.
They would accept metal mags, but not MagPul Pmags.