I had never noticed this before, but the covers make the cab look small from behind. I am sure this is just the illusion of the bed being covered and hiding the height of the cab below the cover. Really makes you notice how small the windows in the back are though.
In June I visited a local (Pembroke, MA) Access installer shop and asked the "Snow Load" question.
The shop manager has this Access cover on his truck that was installed last fall.
He said that last winter's storms in Massachusetts gave the cover no problems, and his truck is outside all the time. On some days he had 24 inches of snow on the cover before he cleared the back to drive.
The cover still looked like new. He uses "303" spray on it ... maybe the spray added strength to the cover ... .
I am still evaluating the pros/cons of the 3 available non-Honda RL covers.