I recently bought a sierra thermal shack and it is turning out to be a nice shack. I took out the second seat and hardware which decreased the weight by just over 15lbs according to the scale, with all steel components. So that gets the weight empty in the high 60's range.
It makes for a roomy shack for one.
I bought an extra front support pole that I use for two reasons. First, it seemed like a really dumb design to have the front support pole in the middle of the door. This way with two front poles I can "frame" the door and have use of the full width of the door. And second it really strengthens the front of the fabric for wind, with no slack in the fabric.
I marked the frames with a sharpie so I can tell with a quick look if they are locked out.
I made some aluminum U brackets and some velcro to lock in the support poles during transport.
I also put in a couple of front grommets for anchoring on the very windy days.
I only have 4 days fishing with it so far, but I like it better than my previous Eskimo Evo 1IT.