Okna v. Vinylmax v. Softlite

I'd appreciate anyone's thoughts on Okna Insul-Tec (~$575/window) v. Vinylmax Hyde Park (~$495/window) v. Softlite Elements (~$575/window)? It's all very confusing to a neophyte. Thanks.

The Softlite Elements is more of a head to head match with Okna's 800 series Envirostar in looks and build than it is with the Okna 500, though the 500 is every bit the performer as the Elements.
Both the Elements and Okna 800 have industry leading air infiltration rates of .01cfm. The Okna 500 has a very good .02 cfm rate whereas the Vinylmax window has a mediocre rate of .17cfm
The Okna and Elements offerings have double pane U-Factors of .25-.26 while the Vinylmax has a .30
In triple/argon glass, the Vinylmax has a U-Factor of .23
In triple/argon glass, both the Elements and Oknas tout a .19-.20 depending on the model.

The Okna and Elements windows are superior offerings IMHO and are priced very nicely. I would choose one of those over the lesser priced brand as I think you'd get the best bang for the buck with Okna or Elements.

The Vinylmax is not in the same category as the Okna and Soft-Lite products in this application.

The Soft-Lite Elements has some nice features and will give you a bit better structural (R-60 vs. R-50) ratings and slightly less air infiltration (0.01 vs. 0.02). Both of these number from either the Soft-Lite of the Okna far exceed just about every other window on the market.

The Okna Insul-tec will give you a bit better thermal data (U-Factor 0.25 vs. 0.26) and a bit higher Visible Transmittance (i.e. more glass) when compared to the Elements.

You can't miss with either window in this case.

Good options you have settled on here.

Thanks very much for your responses.