I was cleaning the PDFs off my desktop the other day, and came across the UN's plan for Small Arms and Light Weapons control. Other than inducing a Red Curtain of Blood moment, it did mention South Africa's registration scheme (as an exemplar, of course...).
Under the current law, a shooter can register exactly one self defense firearm and four(?) sporting firearms. Obviously, two is one and one is none, so yeah. However, it gives the P250 and to an even greater degree the AR15 platforms a new level of utility.
Each of those platforms has a single serialized frame - the P250's frame/fire control assembly, or the AR15's lower receiver. In both cases, the caliber and ergonomics can be tweaked until the cows come home and legally it's still the same gun. Thus, your 'one self-defense arm' can be adapted to:
- Use whatever stocks of ammunition are available (.40's the only thing you can buy these days, but 9 is usually cheaper, to throw out an example)
- Tailor one's response (.223 nightstand gun, 6.8 deer gun, etc)
- Adapt for a different shooter (say your significant other has dramatically larger/smaller hands than you, so pull off the P250 'small' and attach the P250 'large' grips)
I'm sure there's other advantages. I'm a little disappointed* that the P250 frames are not one-size-fits-all - the full-size, compact, and subcompact seem to use different frames - but the AR is as modular as they get; there's no shotgun or .375 H&H upper (yet) but from 10.5" to 24" barrels and everything from .22LR to .50 Beowulf (and crossbow bolts) the AR will do anything a rifle needs to do.
It's a great way to make that 'three gun battery' do a lot more, too. And I suppose, if your S/O isn't gun savvy, you can slip a new upper receiver past them better than a whole new blaster...
* I'm sure someone will bring up the dichotomy of begging and choosing...but it'd be an interesting design challenge to build one usable frame that could handle everything from a 6" open blaster down to a 3.5" subcompact and still be one registered serial number.