I am a fiberglass person, but am warming up to the vinyl side after more research. It is quite clear that typical mainstream fiberglass (pella, marvin, milgard) can not touch the ratings some of the vinyl guys have. I am designing a super efficient house (r-38+ walls, r-60 ceilings) with solar gain options. I am willing to give up my aesthetics issues with vinyl in lieu the thermal advantages. After some research and review reading, Soft-lite might seem like a good vinyl to pursue.

I want to use casements, and going with high SHGC on my south glazing. Unfortunately I have great views to the north I want to maintain, so I am considering triple pane on that side, or possibly some of their upgraded dual pane options.

I am looking at the Imperials, Pros, and Elements. I am not finding many differences between the series on the surface without digging too deep. Can anyone elaborate on these for me? Also does anyone know their pricing structure and how upgrades (such as triple pane or their additional insulating bar) affect pricing?

For example I know a 2'6 x4' casement (impervia or integrity) unit will run me around $350.

any input would be great.