Marvin doesn't make a vinyl clad window, but their aluminum clad is the best in the wood industry. Marvin's Elevate series could be a good option worth considering. Pella is a great marketing company, but few pros here would recommend them. Same goes for Jeld-Wen. I have no experience with Sierra Pacific, but they are budget friendly.

+1 to the above advice.

If I were building in the mountains, I would build with a base material (in my windows and doors) that was completely insensitive to moisture and bugs. Something like Fiberglass fits that bill.

I do not have "Windows" in my name so I would rely on the advice above.

I appreciate the feedback. I was mistaken on the Marvin vinyl clad...it must have been Milgard and that ewas a long time ago. I'll check out the Marvin Elevate series and look at fiberglass options.

Anything Pella, or Jeldwen would be a complete non starter in my book. Sierra Pacific seems to have developed a following but in my opinion a leopard does not change their spots. They were poor all around (quality control, fit & finish & customer service as well as distributor network), and I am not sold that they have changed much.

One of the Marvin family of products would be tough to be critical of, they are all solid products and a solid company.

Thank you @millworkman.