I have, over the past year, and after saving my money aquired three similar firearms.... Glock 35, Springfield XDM 5.25 in 9mm and the M&P 40 Pro Series with same 5.25"bbl.
I had no brand preference prior to aquiring these firearms and I am going to rate them...of course I am in the M&P Forum so you probably already know who wins!
3. Glock 35
I make my decision, primarily because I find the trigger to be the single, most important, element to me shooting accurately. Sight window being second and third balance. M&P has it all...though I like the XDM's feel/balance a little more...it just has way too much creep in the trigger before striking. The Glock could be right there, but it will take investment on my part to alter the trigger...I probably will, but that is sure to run me near $100 to get the pull and crispness I am looking for.
All have performed flawlessly for me. All have qualities I like and qualities I dislike. I like the Glock sight window but don't like the clip release and trigger pull. I like the M&P trigger and sight window but not the slide release. The XDM has wonderful feel and weight/balance, but the creep in the trigger is annoying to me....costs more than the other two also.
In truth, I like all three and will have years of shooting and enjoyment in front of me...I just thought I'd share one guy's opinion.