Integrity by Marvin and run the other way from anything with the Weathershield name on them in my opinion.

I agree on the Integrity as a better choice. Weathershield as a company has had a lot of upheaval in recent years, and the product gets mixed reviews. I've had mixed success with it myself.
It is not difficult at all to find American made windows. The vast majority of windows sold here regardless of material are made in America as there just is not much demand for the higher cost associated with importing a product that may or may not be much better. Some of the Canadian fiberglass products like Inline are very good, but again, there are far more products made here than not.

Thanks to both of you.