My only other "small" pistol is trusty old 659 S&W . I've carried that heavy thing many a day. I always thought it to be a pretty decent pistol and I can hit a target relatively well.
BUT...
I got a Shield 9mm a while back when I decided to carry CCW pretty much all the time rather than just open carry when out in the deserts and such.
I have to say that when on a REST or at longer range the 659 will group a little bit tighter than the Shield but not much.
In actual 7-15 yard "accuracy" both pistols are about the same BUT I hit the targets quicker and with tighter groups easier with the Shield.
I find it easy to carry, easy to draw and acquire a good sight picture and VERY pleasant to shoot in general. I was having a bit of an issue, like many folks, with hitting low-left at first but that seems to have "cured" itself for the most part. Maybe a combination of getting broken-in and the shooter getting his grip and squeeze squared away better.
I just know that the Shield has almost every advantage to ME as a carry pistol and for occasional IDPA style practice / competition . The ONLY advantage of the 659 is it's huge magazine capacity. That, and it's just a purty gun in all it's stainless glory and fine quality materials and workmanship.
Even without the carry advantages of the little Shield, I find it easier to hit the target every time and it has had zero malfunctions for the first 1000 rounds which I got to this morning. It is an excellent defensive pistol IMHO, and MORE accurate than this shooter can equal . I'm quite satisfied with the Shield as far as it's operational characteristics. I WOULD like to see a bit better QC on fit and finish when compared to "high end" S&W pistols of the previous generations. Maybe not everybody wants to PAY for that, but I probably WOULD. I only buy a new pistol every 30 years or so and appreciate a piece of quality when I see it. As far as design and function though, I give S&W high marks.
I'm not a very experienced shooter, and I did NOT stay at a Holiday Inn Express last night ....
YMMV
JMHO