.327 mag can be hard to find, expensive, and there's not a wide variety of guns it's chambered in.
The other .32's it can fire are no real draw. They are unpopular and poorly known. The best thing about them is that you might be able to find them when you can't find .327 mag.
The cartridge is also a bit meh. It's in the same ballpark as a 9mm or a 7.62 Tokarev.
So, if you are willing to put up with all that, what do you get out of it? An extra round in a cylinder. That's it. If you can find ammo.