I'm currently carrying a Glock 19 w/TLR-1 in a DSG Alpha kydex holster (very similar to the Raven mentioned above) probably 90% of the time. The other times, when I need to tuck in a shirt or whatever, it's the same gun sans light in a Crossbreed Supertuck. Neither of these holsters have any retention beyond friction fit, but they both conceal so well it's not a concern for me. Both will retain a gun and loaded mag when turned upside down and shaken.
Despite what your mamma told you, violence does solve problems.
-SO2 Ryan Job USN (SEAL)