i have the shappell dx3000 and is is smaller than the 4000. the 3000 is hard to pull or rather hard to pull all of your things while trying to pull the shelter too. the ski kit helps by staying on top of the snow instead of plaowing the snow like it does w/o the ski kit.
i found it best to bungee a sled on top of it to get my things out onto the ice. using a smitty sled under it and then add a sled on top of that is best in thicker snow.
after it is set up it is hard to move it because the pull rope is only on one half of it and it then has to plow snow.
the poles freeze up where they join each other and you have to try to warm those joints up with your hands to get the four joints unfroze.
you have to know how to make your holes fit the floor before drilling them.
it is not thermal.
you have to take micro spikes off to not ruin the hard plastic floor.
those are the bad things about it.
the good is it has a hard floor. keeps your things dry and feet warm.
you can sleep in it on ice. one of the best to sleep in.
the roof bows make the condensation roll down the walls instead of your person or gear.
it is tall enough to stand up straight.
because it uses 1/2 emt conduit, you can modify it easily. like make wind bars for the sides that get blown in. i made them for both sides.
some have made shelving right over the fishable area.
the carpet is replaceable and so is the bungee cords that keep the support pole together.
the canvas is supposed to be, but i think it was out of stock last i knew when others where looking for it, so maybe check that before buying in case it gets a hole from mice or heat.
i drilled ice anchor holes on the inside in each corner. the thing is a parachute waiting to take off any time you open it in a wind.
try to open the downwind door when going in/out of it.
i ended up putting the long wall into the wind to stop this from happening, but you need to make the wind bars if you do this.
you can add more roof bows.
shappell is a michigan based company that out sourced the canvas to china. it is the lightest shelter (flip over) ever made and popular (fx100).
eagle claw bought them/merged and have been updating the shelters to include thermal version of the most popular. the contract that shappell still holds with china for the canvas will soon expire and then things will change faster for all of us that use the brand with more features.
i never use my dx3000 because it is a hassle to use and move after it's setup and to get all of my things onto the ice.
the best is the fx100 unless i have guests/family then i bring my shappell wh6500 (now offered in thermal wh6500I).
a flip over is so much easier to use in every way other than standing up in one.
what is it about the 4000 you like?