I almost never use the rear sliding window, but definitely love having the option, I did used like 5+ time to carry 2x4's 16 feet long, as long you put a tower on the lower part of the window to avoid scratches you'll good to go.This will be my first truck and I own a station wagon where I can load 10' long pvc pipes or lumber in the vehicle.
How common/practical will be to insert a bunch of 2x6 through the open rear glass up to the dashboard? The sliding rear window area look small and fragile, and maybe even annoying / limiting the rear visibility.
Do you see a way to transport 12'-16' lumber during short trips to the hardware store without installing a rack?
I think that is better having the option and don't need it, than need it and no having the option.