kbm6893:
The M&P9C and 40C seem to be available with and without a thumb safety, and with and without a magazine disconnector. The Hilary Lock seems to also be available with either of those, but also seems to preclude the thumb safety (or vice versa).
Both the magazine safety and Hilary Lock can easily be removed (or added) should you get the itch, but it's (paranoia mode on) not a good idea to remove a manufacturer's safety device. The thumb safety can also be removed easily, but while you can get a plug for the Hilary Lock, the removal of the thumb safety leaves a couple of square holes in the grip frame.
Apex's sear kits will work in all of these models, but you can't use their RAM in the Hilary Lock or thumb safety models. Apex is working on something to go with the thumb safety, but I don't think anybody who's got a Hilary Lock would care anyway.
(If you don't know about it, the "Hilary Lock" is the key lock device - part of the Clinton-era craziness at S&W.)
The Apex kits improve the trigger feel and reduce it's weight a bit. Worth it.... The RAM kit - "Reset Assist Mechanism" improves trigger reset. I think that the latter is a YMMV thing, but the former should be required
....
Regards,