FWIW- I paid $351.00 in October including tax and background check for a Shield with a made date on 4/29/15. The trigger is very good out of the box. With 1000+ rounds it's great. I considered doing a trigger kid but mine is too good to mess with.
If you have an older Shield, look into this DIY trigger work.
S&W M&P Trigger Job
I did have to adjust the rear sight and now it is a very accurate gun!