I've just gotten to the point where I won't buy plumbing parts if they're made in China.
I do a lot of my shopping for home repair items at Menard's, and it's pretty rare anymore to find anything American-made (or at least decent) in their plumbing department -- especially for the pipe & fittings.
The last straw was a few pieces I bought since I was there anyhow -- just a 3/4" tee and a 90. Assembling it, the 90 threaded in very easily (too easily) with no progressive increase in force required, and then tightened abruptly. I used tape, but when things don't feel right, you just know there's going to be rework & cursing. With properly made fittings, this job would have been no challenge at all.
Sure enough, it leaked just enough to piss me off. One droplet every 45 seconds, maybe. No amount of torque & teflon tape would keep it water-tight. Rework with US-made items, and everything's fine.
I had to replace some ball valves a while back, and I had already had bad experiences with Menards' "LDF" brand of garbage valves. I went to an Ace Hardware instead and paid through the snout for some Italian made ball valves. It was worth it, because the job had to be done only once, and they've held up just fine since. (I'd still prefer American...).
I've seen these LDF pieces of crap crumble upon installation. They can't even take the force of normal tightening with a wrench. I've seen one with a pinhole leak at the body of the valve! Nowhere near a moving part. That's how thin the material was. Damn! What are they using for quality control?
What these retailers probably don't understand is that for plumbing (and probably many other areas of home maintenance), labor is the deciding factor. If I buy the Menards Chinese crap, it's almost 100% certain that I'll be doing the job twice. Therefore, I'll shop elsewhere, and I'll buy whatever else I need at the same place. So Menards loses the whole purchase, not just the plumbing.
But as for Chinese plumbing parts -- man, I've had it. No more.