PCC is a great choice for your gf or family member who isn't a "gun guy" and doesn't practice for fun. they'll be much more effective with it than a pistol. muscle memory isn't as important as it is in pistols and it doesn't atrophy as quickly.
I honestly think that applies to many of us. The vast majority of us are no Jack Wilson. Sure I can handle 3" buckshot just fine at the range. When the range is your home and it is now 2-way, I'm not going to be firing on all cylinders. I'm going to be still groggy, I won't be shouldering the shotgun quite right, and I'll put myself on my back if I touched off 3" buck inside my house at 3am.
When you think about it, PCCs are so simple and easy to shoot that you can be in your underwear half asleep, your stance, grip, and shouldering all wrong. Yet still effectively put rounds onto target.
I shot my 9mm AR today. In a rather snarky moment I came up with a bad marketing slogan for PCCs.
“Pistol caliber carbines: combining the weight of a rifle with the marginal effectiveness of a handgun.”
Given that I own a few I’m clearly not opposed to them, but other than as range toys and maybe as home defense guns they don’t seem like a must-have class of firearm. When compared objectively to rifles and handguns they really do combine many of their disadvantages .
This isn't directed specifically at you. It's aimed more at the line of thinking in your post, as I've seen it in many places and I don't want to dismiss it outright. I really wish there was good data on the noise levels of PCCs vs a 16" AR indoors vs handguns. Good data on how disorienting that muzzle blast really is when you're not wrapped in hearing and eye protection. I know just from shooting from a covered range that the AR is just so much louder, more fatiguing, and more disorienting than the PCC in even a partially enclosed environment. If we had better hard data, this issue would be so much easier to discuss in a more objective fashion.
Yes I know that neither the AR or the PCC are hearing safe, but even above 140db there are still degrees of hearing damage. If you had to pick getting hit by a car doing 15 mph or a bus doing 30 mph, you're of course going to pick the car. Yes both are going to hurt, but the car is going to hurt a LOT less.
People say "Don't worry about hearing damage, worry about winning the fight". Try telling someone with severe tinnitus that it's "Not a big deal". Be sure to have someone video tape it.
Yes in theory 5.56 is more more effective than a 9mm PCC. Except that same logic would dictate that we all use .308 AR-10s for home defense. Because .308 is much more effective than 5.56. You could take that all the way until we're using hand grenades for home defense.
Personally, I'd rewrite that saying to "Pistol caliber carbines: combining the ease of use of a 22 with the hitting power of a centerfire cartridge."
The SAS in the Iranian embassy used their MP5s pretty much exclusively in semi-auto mode. Why? Because the low recoil made them easy to shoot accurately and quickly. They swept through and dinked the terrorists with multiple headshots each before they knew what was going on. They didn't care about 200 yard ballistics.
So a PCC gives up a little bit of terminal ballistics in exchange for massively reduced muzzle blast and flash, lower recoil, and faster followup shots. Is it worth that tradeoff? That's up to the individual.