I used aquamax and it was really good, easy and quick to muck out. I am however back on straw as the roof to our stables drips when it thaws and it ruined all my bedding
All bedding breaks down eventually, but some breaks down much faster than others, chopped straw/rape straw for example rots down much more quickly than shavings AND you don't have a massive muckheap like you do with conventional straw.
I use rape straw, rots down quickly and easy to work with.