We have both here in West Central WI, the "common" type is quite common in our area though.
I have seen giant ragweed browsed lightly; however, the real issues is that it can very quickly take over like an invaisive. I have an area that it would grow 8-9' tall and the stalk would get to 1.5' diameter. It shaded and choked out almost all other plants/grasses on a 5-6 acre area with plants growing 6-8" apart. After winter, I literally had to drag a 12' 4"x6" through the field to knock done the stalks.
Does it provide good cover through the winter in your area? Sounds like it might do pretty well for cover....
Yes, but there was never any evidence of bedding. It could block wind, but stalks would tip over. The stalks are real hard and would limit deer access and travel.
Imagine a row of corn, with only 2" per row .... because it dominated and shaded everything out including grasses ... not very accomoding for bedding.
I spent many hours & $$ trying to eradicate ... be careful, very evasive ...