I own a P226 ST (2), a Sig P239, Sig Pro 2022, S&W M&P, S&W M&Pc, Walther P99, and an XD Tactical all in .40 S&W
I can say without a doubt that the M&P is the softest shooting .40 S&W, with the P226 ST a very close second.
The Walther in .40 S&W is pretty snappy.
I used to shoot all 9mm, converted to all .45 and have now gone to all .40 S&W except for my P228 which I'll never give up.
Once I got used to the .40 S&W, it really didn't seem that bad. I shoot the M&Pc and P239 as well as I shoot the P226 and M&P full sized.
Train on it and it's a non issue.