I have a 1.0 Shield that I bought back right after they first came out, when they were VERY hard to find. It took me a few weeks to find anyplace that had any in stock to even buy. IIRC, I paid full price, and then some, for it and the $440.00 mentioned above sounds about right.
The triggers on the original full sized 1.0 M&Ps were awful. I tried them several times because I was trying to get out of Glocks but couldn't stand the triggers. The trigger on the Shield was much different, and better, than the other M&Ps. Very Glock like, with light takeup, a well defined wall just before the break, crisp and well defined (but not the lightest) break, then a pretty well defined trigger reset. Not quite as good as a Glock, but pretty good, good enough that I have been carrying my Shield off duty from my PD job since I got it. I'm very happy with it and it has always worked well, clean or dirty.
I tried one Shield 2.0 example one of the guys at the PD bought for off duty carry. I have to agree with a lot of the above. If you don't already have a Shield, the 2.0 is a very good choice. If you don't want to spend the extra cash on a 2.0, the 1.0 would still be a very good choice, especially since they are so cheap right now. To me, the trigger is very good, but not good enough to switch if you already have a 1.0. The good thing is, holsters, mags and most (if not all) ancillary gear for a 1.0 will also work for the 2.0. S&W did it right when they only changed the internals and left the external dimensions and magazines alone. Either will work very well, it just depends on how much you want to spend.