40 Cal, 10 mil, 45 and 9mm are all full sized guns and hard to conceal. I have the Glock 380, small light and has enough stopping power at close range where the vast majority defensive shooting take place.
The Glock 29 I’m currently carrying is considered compact. I carry it all the time without any problem. I also carry its full sized brother, tbe Glock 20 regularly without any problems. And I think it’s a but of a stretch to claim the .380 ever has enough “stopping power”. If the 10 mm is too much stopping power, the .380 is the complete opposite. Not just my opinion either.