Have you had any time at a local range firing different guns? I carry a SiG P226 chambered in .40 S&W and my G/F carries a Beretta 85FS "Cheetah" chambered in 9mm short (.380Auto). I have a collection comprising several dozen handguns and the most important thing, in my humble opinion, is the way the gun fits your hand and your personal sensitivity to recoil. We enjoy going to the range with ten or twelve different guns and putting rounds downrange, but it's imperative that you spend quality time practicing with your carry.
We're both NRA Handgun Distinguished Experts and did our qualifications with a P226 and with a Beretta 96 (which is chambered in .40, too). As we proceeded through the levels it became clear that the P226 fits me best. And while she can certainly hold her own with the larger framed guns, she's partial to her Cheetah. When it comes down to it, shot placement is most important. Some will go on and on about the stopping power of 10mm, or how you can't beat .45ACP, or how 9mm is the best round for carry pieces, etc. But if you can't hit your target, it doesn't matter
what you're shooting. From a ballistic point of view, a .380 round placed between the eyes is far more effective than
any round placed in the wall.
So my favorite is the P226 in .40S&W and hers is the Cheetah in .380Auto and it's all about fit.
As regards good models, you by and large get what you pay for. A cheap Lorcin isn't in the same quality ballpark as a SiG or Beretta. I'm not a big fan of plastic guns (Glocks, for example) but, still, you pretty much get what you pay for. Spending time at the range with friends trying their guns is, again, a good thing to do. Or visit a range and rent a few different guns. You'll find out fairly quickly what you like and what you don't like. The issues will be all over the place -- too light, too much recoil, grips too wide or thin, no where to put your pinky finger, grip panel texture too rough or slippery, etc. -- but you'll start figuring out what you like and what works for you by eliminating guns that you
don't like. Face time with experienced locals wouldn't hurt, either. (And, of course, if you're in a gun shop, remember that they have an agenda that's centered around profit, so keep the grains of salt handy.)
I find that
Sig Forum is a good resource 'cause I carry a SiG and there are good discussions about virtually every aspect of firearms.