1. Got the money, but not a fool I hope.

My son's a wonderful musician, so I don't need a window that "performs" (sorry, just tired of the promo B.S.). I want the "performance" completed at the factory - a trouble-free window that will last as long as possible at 5000 feet - Calif. winter not too harsh.
This is all pretty new stuff - nothing in the walls for 20 years yet, right?
But I need to decide - fiberglass or aluminum clad? Some say aluminum very good, but fiberglass even better (thermal performance, flexibility, dark colors hold). I don't know.
2. From what I've read, Marvin does a good job with both. Eagle and Kolbe good with aluminum clad. Don't think they do fiberglass windows (??). Milgard fiberglass a step down from Marvin, right, but maybe a good product - I don't know.
Who do you like?