FWIW, my criteria in order of application:
- Reliability. If it doesn't go off when the trigger is pulled, it's just an odd shaped rock.
- Concealability with both clothes to be worn and activities planned. If it won't conceal, it can't go. If I don't have it with me, I can't use it.
- Accuracy. Hits are what counts. Ability to make COM hits with it at zero to 7 yards. More accuracy is better subject to 1 - 2 above.
- Cartridge. The most cartridge that is consistant with 1 - 3 above.
- Ammo capacity. More is better if it doesn't compromise 1 - 4 above.
Speed isn't there because it is a criteria for choice of concealment method. Holster choice and location have more to do with speed than about anything else. Any gun will be fast enough if it is already in the hand. I have 3 hosters for the LCP, the DeSantis Nemessis is the fastest pocket holster I have, so that's what I use when it's in a pocket. If I can carry it in the CrossBreed MiniTuck I do, but that isn't nearly as common as pocket carry for that gun. Holster choice is a different topic.
Order of application is important for selecting guns to buy to cover the expected variation in clothes. Over time, using these criteria, between my wife and I we have chosen 4 carry guns which we can pick from to best satisfy the criteria on any given occasion: G19, G26, P238, LCP. (The P238 is hers - I don't reach for it with anything I'm not willing to lose.) I'm still looking for a micro-9mmP to go between the G26 and the LCP. If I don't find a micro-9mmP I'll probably get a second P238 for myself.
Once one has a selection of guns, the order is important but the choice of the particular gun depends almost exclusively on what clothes are required and the activities planned when it's carried. I pick the most gun that can be concealed from the selection available. In other words, I may be going to the doctors office wearing a sweatshirt, but I'll pack the LCP instead of the G19 because I may have to take the sweatshirt off.
There are lots of other guns just as reliable, or desirable, or acceptable, those are ours, so far. So, in order of desirability, I carry a G19, G26, or an LCP depending on the clothes I will be wearing. My wife carries the P238, or nothing.
All are have been demonstrated to be reliable (200 rounds of breakin including 100 rounds failure free with carry ammo - the reliability test is conducted using all the magazines to be carried in a rotation). Depending on the clothes that suit the occasion I can always conceal at least one of them. All are one of two 9mm cartridges (9x19 or 9x17) because we shoot them better than .40 or .45.
YMMV.
Fitch