I have heard/read about as many failures of the factory shield mag springs as I have of the magguts conversions. Yes, test them as you would any carry gun for funtion of guns and mags.

Question for those folks who would not carry an aftermarket mag conversion.

If S&w would buy, or contract out a vendor such as magguts to produce the mags without any changes to the magguts current materials . Would it suddenly be OK and “safe” to carry this mag/spring combination?

As far as the 8 round mag without the extension rings. Be careful as these extensions are to prevent over insertion of the mag and possible malfunctions!