If I could find cheap Shredded aspen id use it, but the only time Ive seen it was at a show in another state. I used this stuff for a while when I first got lesser and never had any problems with it, but im guessing the finer shred it is the more absorbent and less pokey it comes.
I don't like the fine stuff it packs to tight and makes a wood floor in the tub. I like the big stuff it works great for me.