Down Range Television to the Rescue.
Just watch this video. The guys at Down Range Relevision explain the key points of what this kind of weapon is used for.
Down Range TV
I think this pretty much covers all the little mouseguns. They have their role.
I used to hear the derringer pistols referred to as "gut guns." Meaning that you stuck it in someone's gut and pulled the trigger. Meaning, it was a very close range weapon.
The mouseguns (which have come a long way since the derringers) are perfect for the "Give me your walled," situations (please, I'm not suggesting people play hero). Such confrontations are usually close up and might not allow you to get your standard 45 carry gun. They make a good number of mouseguns that actually fit in your back pocket with a special add-on that makes the gun mostly square (i.e. like you are reaching for your wallet).
As for the 380 caliber, I don't much care for it. Nothing wrong with the round. It has it's role. Just personal preference. I actually prefer the 9mm; very fun for plinking...but it really does have some issues as a carry caliber so I don't carry it (i.e. going through the bad guys and into other people).
I don't quite see how a 380 caliber gun is "slow to deploy." A gun in my shorts pocket is far easier to get to than reaching behind my back and under my shirt. At the very least, it is no slower to deploy than most other conceal carry methods.
Someone once jokingly told me that all pistols are a compromise to rifle calibers.
(The notable exception being the
AMT Automag III which came in 30 Carbine.) But consider that if someone shoots you with a 380, it isn't going to be like they shot you with a BB gun.
Most of us probably won't be attacked by a drug crazed psychopath that required us to empty the magazine of a full size 45 into them (or put another way...most of us won't need that kind of stopping power). However, your grandmother walking to her car at the grocery store at night has a higher probability of encountering some nasty people who want to mug her. She can reach into her purse and pull out a small gun with a recoil she feels comfortable with and defend herself. If your a 6'5" guy weighing 200 pounds, you can handle the higher calibers easier and probably won't have to worry about getting mugged in the first place.
Most people will tell you that shot placement wins the battle...not the caliber. If you shoot someone in the head with a 22 they will be just as dead as with a 45. But please...aim center mass...most people aren't that good a shot especially in these sort of situations...I know I wouldn't be.
I've been looking at getting a mousegun, but wasn't impressed with most until the new Ruger came out. It won't replace my standard CCW, but it will give me some extra versatility. Probably will carry both from time to time.