I own both the SA XDm, and a S&W M&P in .40 and have carried both as duty weapons. Both are great guns and it comes down to personal preference. However, I'd like to talk about the negatives of each pistol. XDm .40 1. A full magazine makes it impossible to use the magazine release button. Because of the increased pressure against the frame, you can't eject a magazine that is fully loaded UNLESS you lock the slide to the rear. 2. The more bells and whistles a pistol has, the more complex it can be to use. I personally do not like grip safeties, loaded chamber indicators, or anything else that is not related to combat pistol shooting. I want a pistol that is hot and ready to go right out of the holster. People say they like the LCI because they can feel if the pistol is loaded. I'm a cop, so mine is ALWAYS loaded. 3. The trigger leaves something to be desired. It has the feel of a "long pull" and causes alot of people to jerk or anticipate the shot, thus throwing their aim off to the left (or right if left handed). 4. It's not an easily concealed pistol because of the size, but for duty use it is fine. It does typically weigh ~8oz. more than other .40s of the same class. M&P .40 1. The first time mine got wet from being out in the rain on duty, the slide near the rear sight started to rust. A quick coat of oil solved this problem and removed the rust. 2. I missed out on the 2 free magazines offer because I bought mine the month they were introduced into production, before the offer was available. S&W would not send me 2 free mags even after a letter praising the pistol for LE use. 3. I have medium sized hands, and with any of the 3 backstraps, my left thumb does not fit comfortably against the frame as it always hits the slide lock and feels awkward. The pistol could be 1/2" longer and would be fine. Summary: Between the 2 for duty use, I have to go with the M&P. It feels better in the hand and the point of aim is more true. The felt recoil in the .40 is noticeably less in the M&P and for the time being it has more accessories available in terms of sights, holsters, etc.