We've found double pane is far more important in an RV than in a sticks and bricks. In an RV you are usually sleeping/sitting much closer to the window than in your house. We really noticed the difference when we switched from a Class C with single pane to a Class A with dual. We will camp in cold weather and we were pleasantly surprised at the difference we noticed. Our 1st Class A had foggy glass and I did the repair myself. I used a razor blade to cut the spacer out on the top and bottom (so the panes were still together) and pulled a rag with Turtle Wax Chrome Polish on it between the two panes of glass with a coathanger. Takes a little while. Two people makes it easier. Was told the glass was 'etched' and would not clean up, I found that not to be the case. The Chrome polish removed the crusty white deposit then I replaced the spacer and resealed. There are two steps, replacing the spacer making sure it's a quarter inch in from the edge of the glass then filling the remaining gap with the sealer. Once I did that and the sealer dried, I used the razor knife to dig out the old sealer on the two vertical sides (leaving the old spacer) and applied new. The sealer does the real work of keeping moisture out of the space between the glass. I would suggest you do the repair on a dry day to minimize any moisture getting trapped. The spacer is supposed to have some desiccant in it to absorb any moisture that gets caught in there as you seal it up. Worked perfectly for the next 3 years until we traded on a new RV. If you've pulled the windows already, you're halfway there. To get the glass out, there will be splice in the window frame that you unscrew that will let you spring the frame open and remove the glass. $165 each doesn't sound too bad if you both still work!
