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I need help to find a gun that fits my needs and the following specs:
Caliber: .40 S&W
Magazine load: min 11 (more is better of course)
Safeties: I do not like manual safety switches. Grip safeties are OK.
Size: up to 4.50" barrel. Smaller is better.
Ergonomics: It has to have top notch ergonomics.
Trigger: Consistent pulls for every shot. Short and light pull. DAO only.
Not required but as a nice bonus it would be good to have:
1) extended lock slide
2) a) ambidextrous and b) simple magazine release style. I prefer push button styles but lever type is fine if it's easy to operate.
I personally have been most pleased with the H.K. P2000, which holds 12+1 rounds of .40 S&W, has ambi controls, no manual safeties, polygonally rifled 3.7" barrel, short trigger reset, and I.M.O. has the nicest ergonomics if you decide you can handle a lever type mag release. Mine's a V3 which is T.D.A., but it's also available in L.E.M. that has a consistent pull from first shot to last per your specifications. The H.E. finish is not the most durable out there, but good enough I.M.O.
I'd also be sure to try the Sig P250 that B.W. recommended. It's much improved over their SigPro, which was a bit heavy for a compact polymer at 30oz with
empty mag. The P250 compact O.T.O.H. is 25oz and 13 x .40 S&W. Although F.Y.I. I've been no more impressed with Nitron than H.E. finish, Y.M.M.V. Similarly the Walther P99 in Quick Action ("D.A.O." striker fired, 4.17", 12 x .40 S&W) is another high quality option. Otherwise, the F.N.P. 40 is available in D.A.O. (4", 14 x .40 S&W), as are S&W's metal frames (4", 11 x.40 S&W), their polymer M&P (4.2", 15 x .40 S.W.), and Springfield's X.D. (4", 12 x .40 S&W) all meet your specifications as well, but I'd probably avoid Taurus, Ruger, C.Z. and Kahr for what you've requested, but that's J.M.O. and Y.M.M.V. If you dropped the 11 round capacity requirement by a couple of rounds, it would open up a few more options (for instance subcompacts by the same makes if you are O.K. with "pinky-danglers" or gripping mag extensions).
I am not particularly comfortable with the GLOCK "safe action" trigger outside of range and game use, but if you are they make the most durable, toughest finish, and are tops in size & weight to capacity ratios. With the shortest O.A.L. yet longest barrel in a compact (4" barrel but only EDIT-6.85" overall), the GLOCK 23 is "D.A.O." striker-fired and holds 13 x .40 S&W. It also has the polygonal rifling like the H.K. which makes up some velocity lost in compacts and subs. GLOCK has the lowest bore-axis, a very short reset, and despite the infamous "2x4" shape, they are actually pretty thin (1.18" overall). 0.T.o.H. GLOCK ergonomics, aesthetics, grip angle, and trigger are highly Y.M.M.V. The 22 has wider finger groove spacing, and is a very smooth shooting .40 S&W (which B.T.W. while "full-size", the 22 still meets your criteria). This is the highest value I.M.O. and best fits your requirements. So I would be sure to check out a 22 or 23, the P2000, P250, and the P99. You can't go wrong with GLOCK, H.K., Sig, and Walther I.M.O.