No 23 here but I have a 19 and a 30 both of which are comfortable, 100% reliable, and shoot more than accurately enough for my "OK" skill level. Admittedly I am more accurate with 1911s, but the difference is not significant for HD work. The difference between a 2.5" group and a 1.5" group isn't going to make a difference (not that I kid myself into thinking I could necessarily keep EITHER grouping in a live shooting situation). However the difference between always shoots and occasionally doesn't MIGHT make a difference. SIG an Glocks are both renowned for always going bang, so you're onto two winners there. I second FWIW the idea that overpenetration is MORE likely on a 9 or .40 than a .45. Stick some 230gr DoubleTap JHPs in that P220 and you're gold.
You'll get a lot of bad press on the glocks for a few basic reasons - generally
a) an emotional (not the same as irrational, but can also be that too) distaste for "plastic" guns.
b) reported instances of "kabooms" which almost always center on overpowered reloads and in any case tend to be third hand anecdotes.
c) point angle - a rather subjective opinion on whether the gun "points" naturally when you swing it rapidly on an imaginary target without aiming. A lot of veteran shooters (which I'm not) say the Glock points high. I have no reason to doubt them but it doesn't do so for ME. Try a G23 in a store and (please very carefully and with advance warning to the guys on the counter) rapidly point it at a safe "target" without actually aiming THEN check the sights. If you are close, the Glock works fine for you. If you are way high then you may want to stick with the Sig brand. Personally Glocks point BETTER for me than Sigs do, but I'm probably in the minority and definitely not relevant for you. However neither are the claims that Glocks DON'T point well for other people.
d) Perceived greater incidence of failure from anecdotal reports. Remember that the plural of anecdote is NOT data. There is a reason you don't see as many Mercedes Benzes broken down than you see Chevys, and believe it or not it's NOT thet MB's are more reliable (although they probably are more durable). Trust me on this MB's certainly have some reliability issues, but there are a tiny fraction of them compared to how many Chevys there are on the road so what are your chances if both break down equally or even if the MB's break down slightly more often as a percentage? Think about that for a minute and then remember that in the semiauto handgun world, Glocks are the Chevys in this analogy - and far outsell other brands.
EDIT - how could I forget e) The trigger pull. This one alone I have some sympathy with. There IS a fair amount of creep and a spongy break on Glock triggers. If you're a precision shooter used to the 1911 short pull SA trigger for decades, you're not going to like Glock triggers. They work fine but they feel a lot less clean. I prefer it to DA/SA guns or "crunchentickers", or even DAO guns (without starting the argument that technically speaking a Glock may or may not be a DAO - it certainly doesn't feel like the traditional DA trigger) but it's hardly the best feature of a Glock for sure. Functional. You get used to it. Not great though.
Glocks are fine guns with excellent reliability, a laughably easy manual of arms, great durability, moderate cost and perfectly commendable if not bleeding edge accuracy. They are not "perfection" except perhaps in the utilitarian sense of their intended purpose, but they sure as hell aren't junky or unsafe either.
