Being able to choose my caliber and barrel length and have the new port drilled in the "off" position is definitely a plus. And the extra power piston spring that comes with it is a nice touch. I'm not a professional by any means, but I do like to tinker around with firearms and try to improve their performance. That being said, I always make sure to use quality equipment for my drilling projects.
Practically speaking, the Bren 2 doesn’t really qualify as a multi barrel / caliber gun. They recently listed a “change kit” on their Webstore to go from 7.62x39 to 5.56 (wonder why?) for $900. But as usual, it’s out of stock, as are the vast majority of Bren 2 parts, including essential replacement items like firing pins, ejectors, extractors and the pins and springs thereof. I’ve been on the waiting list for a couple of years now for many parts. Of course, for $900 you could also buy a pretty good brand new functional AR.
There’s also a company called Mos-Tec that will make you a barrel of whatever caliber and length for @ $600 but you have to supply a Bren 2 barrel extension and gas block (also usually out of stock), which will bring it up to @ $900 for the barrel, but with no caliber-appropriate bolt.
If you want to get into the multi barrel / caliber game, you should look at the Robinson Arms XCR, which has several configurations of barrel / caliber swap kits readily available on their website (contingent on any back order waiting lists) for about half the cost of what CZ lists on their limited Bren 2 “change kits,” which seem to be perpetually out of stock, like most of their Bren 2 parts.
