Diamondback HD is installed, minus the full cab guard. I hauled a dining room table and chairs with it the next day over 650 miles with no problem.
The cab guard instructions suck IMO. I went step by step, following each direction and recommendation. There is a point where I had to drill two holes into the cover. The directions say to make sure nothing will get in the way of the "bolt." Well, there are so many screws and washers that come in the kit that I didn't think about clearance for them too...drilled two close to a welded crossmember and of course, a gigantic washer needed to go there. Not to mention, the cab guard gussets flared out so that I would have to do some extreme bending just to get them to secure to the cover and not impede tie down cleats. Fortunately Diamondback has a great customer service and wants pictures/is working with me to fix the problem. I foresee them having to send me a new front panel and cab guard that fits right.
That aside, I love this cover and would buy it again. It allows you to haul heavy loads and weatherproof cargo underneath, something no other bed cover can give you.
I will post once picture I have taken after I first installed it then with the whole ATV package set up after I get this cab guard issue taken care of.