Thunderwear and the little Colt
I sometimes carry a Colt Government Model 380 (and a spare mag) in my Thunderwear. Before I retired, I carried it at work every day in the Thunderwear. No one knew about it in all the years I carried it. Today, I have a dentist appointment and will carry the little .380 in it. With practice, you can get to it in a hurry. The only issue I had was taking a squirt in a public restroom. You need to unzip and flip the holster up to get your business taken care of - or go into a stall for privacy.
It is a good way to discreetly carry a smaller handgun when you just can't carry on or in your belt due to clothing requirements. In my opinion, it is much better than an ankle holster (which I have but seldom wear).