In my humble opinion there is no choice to be made, Kolbe without a doubt

That is what the architect said too. But, the GC said to stick with Pella since that is what we already had and the "brand" name. Can you tell me why Kplbe wins hands down? I'd appreciate it! Of course I need to decide in 2 days! Thank you!

Search the forums and you will see what I am speaking. Kolbe is a quality product with a good reputation and good customer service in general, and Pella not so much on all accounts

Kolbe probably cost more than Pella, but not by much.
I agree with the forum, go with Kolbe & Kolbe.
I used them about 10 to 15 years ago on an Historic
Home in North Jersey and they still are like new. I
haven't had one service call on that home to date.

All the Best,
The Porch Guy

Here is a link that might be useful: My Album

Kolbe, for certain. Pella may have the name outside the trades, but inside the trades Kolbe is the hands down winner - much better quality, much better post sale support, generally a better company and a better window.

Have not used Kolbe and only seen them as displays, but the quality looked impressive.
Pella on the other hand is some of the worst junk out there.
I speak from first hand experience as I have installed top of the line Pella Architectural series windows and french door in my new addition. These windows are garbage and I will never ever buy Pella again. My issue with them mostly is the lack of attention to detail. Issues like hardware being screwed on crooked, bed miter joints. The overall construction is however functional. After I have spent massive amounts of time correcting them, the windows have functioned fine for the last 5 years. Still I will never forgive them for the product that was delivered.