Why would you want two different barrels rather than two different guns? IMO worse case scenario your back door gets kicked in, you grab the glock and grab a mag, and you grab the .40 when you have the .9mm barrel in.
Unlikely to happen but I keep a gun and extra mags in a particular area of the crib for quick access. In my old crib I'd toss my .40 and my 9 in the same top drawer they are completely different brands but if I had a glock with differently mags I can see mixing them up accidently. Unless your meticulous .
Well my my glock 19 is my bedside gun for now. Imo you should always have your bedside/shtf/home defense gun good to go.
The thing is the used very good condition glock 22s are going for 299 right now. The police and feds are dumping 40 for 9mm. Those conversion barrels are 90-100 bucks so you essentially are getting a $450 glock 22 and a $450 glock 17 ($900 total) for 400 dollars lol.
I feel like a thief for doing that lol.
The conversion shoot flawlessly too. Oh and if you want to shoot .357 mag you can buy a barrel for that too so you have a three in one lol.