There is no doubt that Sig royally screwed up their approach to the US 55X. The subject has been beaten to death in multiple discussions across the web. However, the guns are not bad guns. Aside from the canted rail issue, which was fixed on later guns, I don't know of any real negative, aside from a total lack of respect for the Swiss guns, which they should have just imported or copied verbatim.

I have seen/experienced parts failures, but they were extreme examples of abused guns. As a general rule, the guns are solid.

There was also a steel reinforcement added to the 556R "gen2" magazine well, which addressed an issue with the first batch of those rifles.

Ironically, the dreaded canted rail guns are actually some of the more desirable ones, IMO, as the early guns contained a number of Swiss parts, and had a neat parkerized finish, with more appealing receiver markings to boot.

Ah, I did just remember a gun that I have was lacking welds on the forward portions of the receiver carrier guide rails. That was a big screw up, I do concede.

There was a definite lack of consistency in construction, during the rifles' production.

I don't have a dog in the fight. I just think people are typically far too hard on these guns. To say that you wouldn't consider buying something like P365, because of the "556 fiasco", is a bit crazy, IMO.

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Fair point. But why invest in a company that doesn't invest in its customers? In contrast, HK supported the P7 series longer than SIG had the 556 in production.