Would you need to return your trigger to OEM if you have to send it in for warranty repair?
The M&P 15-22 may be "just a plinker", but I predict that in a short while the 15-22 will join the ranks of the Ruger 10-22 as one of the most "souped up" 22's ever. This from a new 15-22 owner and a Ruger Charger owner that has twice the original purchase price invested and worth every cent. Face it, we're all a bunch of junkies that just can't leave well enough alone. I haven't got to fire the 15-22 yet and already I'm drooling over what future upgrades will be offered.
i ordered new trigger and hammer springs to modify so i could leave the stock springs alone in case of a return. i doubt s&w will notice i polished the sear/hammer interface.
the extra springs are cheap (about 3 bucks).
realistically, a $450 plinker isnt really worth buying a aftermarket trigger for.