I have two of them. The bottom sides have started to bend in (5 years old now and started to bend in bit within the first year) so a bit harder to flip over the bale. Also the bottom of the "windows" have cracked from being flipped over and horses pushing on them. They keep the bale dry and horse out of it. I think they are over priced but a decent product. The Hay Huts I've looked at seem studier, a less bendy plastic. Maybe heavier and I know they were 6" taller as well when I was researching them. Shipping was more for them too. But I think I'd go with a hay hut if I had to do it again. I bought mine when they'd pretty much just come out.
I've used both. We had to leave behind our Duplessis when we moved from OK to Washington state where they sold hay huts.
Both are pretty much the same thing, the hay huts I think came second and improved a few things. Over all they work the same and I love having one.
The protect hay (round bales or piled square bales) from horses peeing on, pawing at, or otherwise ruining the hay.
The hay stays pretty dry and the wind can't blow it away.
My favorite? It stopped the bully gelding from being able to chase away the other horses. Since their heads have to be in a window to eat, he had to first back out and try to chase them away, and put his head in. Meanwhile, they would see him start to back out, move away and go right back to eating. He gave up, it was to much trouble.
I've had a Duplessis hay hut for 4 yrs and last year bought a green Hay Hut because we got a local dealer. The green one is a bit taller but the sides seem to bend in at the bottom more than the tan Duplessis one. I like the Duplessis one better for that reason.
They do save a lot of hay but snow can blow into them. For years I just had round bales out on the ground and the "hay huts" have probably paid for themselves now. And with the price of round bales going from $35 six yrs ago to $65 last yr I am very glad I have the huts.
I also like having hay available to the horses all day so there is less tree and fence chewing and less getting into trouble period.