I returned Cavallos back to the store very next day. VERY bulky, moves on hoof, very rigid, etc. Junk...
I've seen Old Mac's and they are very bulky too AND very hard to put on.
I've been using Easyboot Bare all last summer everywhere: rocks, mud, sand, and they did perfect (still like new). The gator keeps them in place even in worst muddy conditions. Takes me 1 min to put on, very light and small. Happy overall. I also got a pair of Easyboot Epic (for my other horse). OK, but I don't like much that wire-clip combo on front.
Never tried Boa, but heard they are good.