I had looked at those years ago when I had smaller truck. Security and access were the negatives for me. I ended up with an aluminum contractor with side doors and full rear double doors. It was light enough that I could raise it up on my back and walk it off the back of the full sized short bed truck myself on to saw horses. My first mini truck had a fiberglass canopy the was so heavy that two young guys were required to load and unload it. I have seen some flat bed covers for sleds similar in design to your soft canopy but was put off by the price (even though it would be handy for my flat bed trailer and current truck).