I've fired the XDm .40 and the XD subcompact 9mm and the M&P .45
Best one to shoot in my opinion the M&P .45... since that caliber isn't one of your choices I will say that if the smaller caliber M&P's have the same grip and trigger pull and break then they have my vote.
M&P's are very reliable and that .45 was a dream. The only polymer .45 that shoots better IMO is my USP .45
But, if you don't go with the M&P then I would choose the XD. I'm not a big fan of either the XD or the XDm but the subcompact 9mm XD I was firing was a lot better than the full-size XDm that I tried...
Just my thoughts..
Goodluck bud!
P.S. plouffedaddy: thats a great picture