I have a few CMP M1 Carbines. I bought 1 each for my grandkids. I have Inland and Underwood receiver barrel carbines. The rest of the components are a mix of all manufacturers. As I understand it the carbine was manufactured so that the parts from one manufacturer would fit into any carbine produced by any of the other manufacturers.
The tolerances were flexible. I suspect whichever receiver/barrel one gets it will be just about as good as any other receiver/barrel combination manufactured as the requirements for each of the manufacturers was the same. If the receiver/barrel does not match, the barrel is worn, or the parts slop is on the order of maximum + matched with maximum - in the rebuild, then it might be a 'Worst case scenario'.
I have noticed that one Inland shoots better than the other Inlands, and one shoots worse than the other Inlands. The same is true for the Underwoods. However I also have noticed that the best Inland shoots about the same as the best Underwood, and the worst Inland shoots about the same as the worst Underwood.
I like it for Coyotes under 100 yards.
When the number of people in institutions reaches 51%, we change sides.