The best Double Pane Slider and Picture WIndows from Sunrise is Omega 12 with Interior Low E option. The U-Factor is 0.25 and 0.22 respectively.
The best Double Pane Slider and Picture Windows from Polaris is Ultraweld Supreme. The U-factor is 0.27 and 0.26 respectively.
If I want U-factor of 0.23 or better, I need to go Triple Pane with both Sunrise and Polaris, which will increase the cost. I'm installing 2 picture windows and 2 sliders
The Provia double panel(Endure ComfortTech-DLA-UV-HC) seems to have surprisingly good U-factor. Their sliders and Picture windows have U-factors of 0.23 and 0.22 respectively.
Should I go with Provia Double Pane? or should I just stick with Sunrise? SHould I do Triple Pane? I'm soliciting thoughts

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