This is not my house. This house has been heavily remodeled inside, but has the original glass end wall that my house had when built. This is stick built, single pane, plate glass held in by wood stops and french doors. Mine already had rather thick vinyl replacement windows and fiberglass French door inserted into this.

I would like to replace the French doors and the adjoining window on each side with a sliding door, and do fixed glass on the ends and top.

Because the slider would be 10 feet total, and the non standard sizes of the others I was looking at Marvin Infinity Replacement Low E3 or Low E3 ERS for the replacements.

Would they be good for this application? The top is the original condition, the bottom photo is the configuration I would like to do, I think. I realize the mullions would be thicker, I don't really have the budget anymore for some custom direct set sort of thing with minimal muntins. This is really the last thing that needs to be done in a long drawn out restoration.

The fixed panel with be the one with the arrow on it over the stairs.