The S&W is a good contender. Personally I think S&W seriously dropped the ball with it between the early guns and now, but the word is that they are taking it seriously again and fixing the issues.
I definitely agree that it's an advantage to offer options, but that's mainly an advantage for the company. An individual user can tailor their skill set to whatever gun they like, so for me personally, it doesn't make a lot of difference if the people who build my gun also build it with a bunch of different options that I didn't want.
But I am glad that they are trying to sort out their problems, because the more competition, the better.
At the moment, I think the M&P series is at least as good as the Gen 4 Glocks, but the 9mm S&Ws are having accuracy issues from the early-unlocking barrel, I believe.
I think the .40 and .45 options are not suffering from this and as a result I believe they're equivalent or better guns than the G22 and 21 - although I think the Gen 3s make this harder to tell.
I consider these guns roughly equivalent, is what I am trying to say. Whichever fixes their fleas first gets my vote.
I will say this: the M&P was a step forward from the Glock when it debuted. If S&W had worked hard on it, consistently, it would have been a better pistol than the Glock, I think. And that is mainly because they looked at the deficiencies of the Glock and tried to correct them. So there is real value in being responsive to customer demands. Hopefully the gun will continue to improve, if for no other reason that it will force Glock to get their #### together.