Just make a prioritized list of your top 10 requirements. Then pick which rifle meets each requirement more. Rank 1 requirement gets 10 points, rank 2 gets 9 points, rank 3 gets 8 points and so on. The rifle with the most points wins. In reality though, most people will just choose the item that "sings" to them more.
The XCR has the best ergonomics out of all the black rifles. The VZ58 has the best reputation amongst all military issued 7.62x39 rifles. As a fun plinker, I think the VZ58 wins. As a competition gun, I think the XCR wins.
Some example requirements: lightness, balance, ergonomics, accuracy, reliability, ease of maintenance, durability, resale value, compatability of parts with common standards, trigger feel.
To me, the XCR wins ergonomics, ease of maintenance, resale value, parts compatibility and trigger feel.
The VZ58 wins durability (anecdotal evidence, XCR is still pretty good too), reliability (anecdotal evidence, XCR is still pretty good also)
The rest is a tie IMO.