My first carry weapon was a .22 - I, a person who had zero gun experience, bought it based on a youtube video. I still love my P22, but it's not my carry gun anymore. I bought my second gun, a Taurus PT140 Pro, sort of on a whim. I had been investigating CC options and was actually leaning toward several other options, but a used PT140 with a near flawless reputation came up for sale and I snapped it up. It was probably my smartest purchase - its a wonder for carry, accurate enough for me, and was cheap enough that if it ever has to leave my side, I won't be bankrupt. I added a used Springfield XD-40 to my collection this past week, which threw out the major factor that drove my PT140 purchase - the manual safety. The fact that it had no safety bugged me for awhile, but after shooting my friend's gun at the range, I began to like the fact that it was easier to shoot than my Taurus. When he told me he was getting rid of it to facilitate a switch to 9mm, I snapped it up.
Overall, I am an impulse buyer at heart. If it goes bang, and it's in front of me, and its for sale, and its in my price range, and it doesn't completely repulse me aesthetically, (Beretta Px4 Storm, I'm looking at you - I wanted to love you, but it will never work) I will probably buy it. Overall, the only thing that could sway my choice, if offered two, would be accuracy.
I still lust after a Walther P99 in .40. I don't care if I can't hit the broad side of a barn with it. I love that gun, for some strange reason.