I just bought an M&P 9mm Shield on Saturday, pick it up Tuesday. From the M&Ps I have shot before, I like the trigger and ergo. To me, it is a good effective carry gun, that matches or beats the qualities of others for significantly less cost.
In terms of trigger feel, I liked the Sig P938 better, but it is more expensive. The P938 (9mm only, SAO) has some of the look and feel of a 1911, although internals are completely different. If I recall correctly, the P938 has "cocked and locked" capability. It is metal frame construction, but as light or lighter than the shield. There are a few youtube reviews out there for it.
The P938 has a sister model, the P238 which is slightly different exterior, and comes in 380acp.
The PPS and XDS are also significant players in this size. I liked the feel and layout of the PPS. XDS offers this small size package all the way up to 45acp, whereas the shield stops at 40. I'm not sure about the PPS offerings.