G19 is an ideal size for carry yet still handles pretty much like a full-sized pistol; 15 rounds, light rail for bedside use, fairly cheap, parts are fairly cheap and available and easy to work on. Although I don't much like the triggers even with the 3.5# installed.
Seems like QC has slipped with many brands to where I think HK has most everyone beat on out of the box quality and long term durability. Since price is less of an object in the "just one" scenario the P30 or P30L might be a contender but I don't have experience with it yet.