RayH,
I love it... I bought it last year right before a vacation to Colorado for additional storage room while 4-wheeling in the mountains. I haven't taken it off since. It has held up very well so far and does a good job of keeping all the wet Louisiana weather on the outside. I did not see an option for a pass-thru window (would be nice though). The only drawback I can think of is, it gets pretty stiff and is sometimes tough to un-zip in the cold, but that is not very often a problem down here...
Chip