When I decided to start carrying every day about 4 or 5 years ago, I bought a Ruger LCP. Great little gun, easy to hide, comfortable to carry...but hard to shoot well and chambered in a pretty puny caliber to boot. Then I got into j-frames...I've owned 15 altogether, Chiefs & Centennials, and currently own 5 Chiefs. Not quite as easy & comfortable to conceal A-IWB as the LCP, but chambered in a much more serious caliber & easier to make DAO hits with.
But with that said.... the LaFrance 9mm Nova (see thumbnail) was a custom-built cut-down version of the Star BKM produced back in the early 1980's. About the smallest serious-caliber pistol available back then, I always wanted one but couldn't have afforded it plus they were sold to LEO's only. Then in 2012, Sig came out with the P938-- darn near a knockoff of the Nova. I really like the way it looks and handles. I finally bit the bullet and ordered one up last week and should be getting it before too long. A single-action 1911-ish design with a 3" barrel & alloy frame, weighing 16 ounces. I have high hopes that it will be almost as easy to pack as the LCP (and easier than the Chief), and I'm pretty certain it will be easier to shoot well than a DAO autopistol or revolver.
As far as caliber goes, a 9mm 115 gr JHP at 1200 fps has about the same momentum (power factor) as a 38 spl 158 gr LSWC-HP at 850, but almost 45% more muzzle energy-- plus a better chance for proper expansion. And the 938 carries 7 rounds vs a Chief's 5.
So asuming it gives 100% reliablity, it will probably become my new EDC. I'm looking forward to getting it and giving it a workout.
FWIW here's a photo of the LaFrance 9mm Nova, circa 1982.