First off the specs.
Layers: Single Layer
Outside Fabric & Color: 1.8 Night Grid
Suspension: Cinch Buckle
Asym Lay: Right
Ridgeline: 2pc w/split at foot end
Extra Zipper Sliders
Net: Left side
Overcover: Left side
Type: Upgrade to Pack Hooks
Description: Netting on last 12" of overcover
So far so good on the overcover vent window. I received the DangerBird last Wednesday. I spent Wednesday (31 degrees), Thursday (40 degrees) in my garage, and last night at Antietam Shelter (mid 30's - low 40's). Thus far I have been able to keep the overcover fully zipped with no issues. The vent seems to be perfect. It is keeping in a considerable amount of heat. I woke up this morning half covered up thinking it was rather warm, unzipped it to stick my head out and I could feel a big temperature difference. I haven't had any condensation issues, perhaps it hasn't been cold enough out. I don't have any experience using an overcover other than this one so I really don't know, but it's working out great in this weather. I have never been more impressed with any cottage vender. I can't begin to say enough about PapaSmurf and MamaSmurf.
Here are some pics that Randy took last week and some from this morning when we were packing up.