I posted on this a few weeks ago as the yard where my boy lives introduced it as an alternative to shavings, which are getting expensive! I tried it for a while but wasn't very impressed so have gone back to shavings. But having said that a few folks on the yard do use it all the time, deep litter with it and are ok with it. I think my issue was that I mixed it with shavings which didn't work. Also, a person with a very wet mare didn't like it at all because it wasn't as absorbent. I think it very much depends on your horse, your management and how often you plan to dig it out. Not sure any of this helps at all but just my experience.
Have you tried hemp?? I semi-deep litter on hemp (droppings out everyday, wet at weekends) and I love it - MUCH more absorbent than shavings and makes a nice solid but comfy bed. I put it straight onto the floor as I don't have mats and would recommend it.
I put 4 bales in initially....it will take about 2 weeks to bed down. I remove droppings every day and add a new bale probably every 3/4 weeks. I take out the wet once a month (usually about 2 wheelbarrows) and this is generally when I put the new bale down. It is SO cost effective, takes seconds to muck out and pony is always clean. He's very wet and the bed absorbs it well! It doesn't smell even after a month, and isn't dusty