Hello, I work for the Durango and Silverton! The Silver Vista is all open air with a glass room to top it off. It's a more authentic Denver and Rio Grande Experience. The Knight Sky however, IS ALSO OPEN AIR DURING THE SUMMER! I don't know when you are riding but they take the windows out and make it more like the Silver Vista. The Knight Sky boasts first class airline seats as well as the trains largest viewing platforms. If you are riding in the winter than they do put the windows in. making it nice and toasty. Take it from me, that thing can acutally get hot on a cold, winter Polar Express night. Hope that helps,
Durangokid123