Our own shawn mccarver has a couple threads on the one he bought:
Model 66 for 2014
Model 66 for 2014 - Holsters caution
I've handled though not shot one, and was impressed with the overall fit and finish. I did find the larger and longer two piece barrel made for a front heavier 66 than its older brothers and didn't quite like the weight distribution, but nor did I find it a dealbreaker. A 3" set-up I think is closer to ideal, and I'd love to see a fixed sight version with a pinned front sight.
Trigger was decent but a bit heavy and vague, which I find common in most new S&Ws of MIM vintage; they can certainly be improved with use and a little correctly performed stoning.
I loathe the lock for all the usual reasons -- mechanical, political and aesthetic -- but could also live with it in return some of the legitimate benefits of the modern S&Ws, like CNC precision, impressive accuracy and a lifetime warranty.