In my experience, the coldest areas on the window (including the bottom edge of glass) will be in the ballpark of 30 degrees warmer then the exterior temperature in the winter. Your windows may be a little colder than expected. While Marvin makes quality windows, "airtightness" isn't exactly their forte, especially for sliders. Based on the area that you are showing, that would be a reflection of the window itself, not the installation unless it is out of square causing the sealing issue.

Energy Star's air infiltration limit is an awful .30cfm which EVERY window on the market has to meet or beat, so unfortunately that isn't something that would ensure an airtight unit. Most pros in the know would speculate that the poor air infiltration ratings of the big name brands and their influence are the very reason for this. Supreme irony given that the home performance industry is centered around air leakage more than anything else.

Pretty normal points of infiltration on a slider. Some are better than others, but nothing there is jumping out at me.

Thank you both, this is helpful to know, and I probably won't make a big stink with the installer then. Bummer that our installer wasn't more forthright about this with us, though I know people don't like to hear this information when shelling out for a major purchase. I had hoped for better from Marvin, especially given the cost!

I'm going to take my thermal camera and look all around the frame to see if any additional issues jump out, but I agree that what I've done so far indicates that coldest parts are within the window itself, so no indication of install issues.

Any suggestions to try and minimize the cold near the windows? Add some more rope caulk? I was thinking of getting some of those insulation socks to fit in the track area during the winter?

Thanks again.