Just reading through your posts. My two bits: I've carried a number of concealed weapons over the years, including a Wather PPK 380, a S&W .38 snubnose 5 shot, and a S&W .357 magnum. I've used Glocks. I now carry a Springfiled XD45 Tactical and prefer it over all the above. Out of the box it out shoots every other handgun I ever owned.
The XD is narrower than the Glock and feels better in my hands. It seems to be more sturdy and has taken some abuse with no damage. It is a beautifully balanced weapon and seems to jump on-sight. If protecting yourself and others is your priority, then you might consider the XD45 has a 13 round magazine. With one in the chamber, perfectly safe in this weapon (dual safeties), you have 14 rounds that can be fired as fast as you pull the trigger... and as accurately as you are accurate.
I prefer the .45 ACP because of its well known knockdown power over a reasonably long distance (I saw a big, outraged man dropped at 75+ yards with one shot in the thorax). It is a THUMPER!
Concealability? The XD45 Tactical is a big gun. I carry it side ITW everywhere and have not known of anyone spotting it... even police officers with whom I associate. (I found a perfect form fitted leather ITW holster for it on eBay if anyone is interested - under $30). It is remarkably comfortable to carry.
In the end you need to go with what feels right to you, but keep in mind your objective. Cost, appearance, and other factors are secondary when you are looking to stay alive.
Okay, a bit more than two bits!