I do not like any of them but If I must have one, I would get the XDm.
I have shot the XD (9mm and .40) - it is OK.
M&P (9mm) - bet grip fit but bad trigger. Sold mine.
XDM (.40) - Very accurate. Trigger was not clean.
Have you look at a Walther P99? I have a DA/SA but am considering getting the PPQ with the glock-like trigger.