Cypress for sure. I went the cocohusk route and hated it. It gets stuck to EVERYTHING. Water changes were a disater, and it was always in his water, even immediately after the new water was put in. Dovah stopped eating because his rats would end up with bedding on them while he constricted. It was also always in his heat pits. and it was impossible to find his poops because they were always covered in bedding.
Cypress looks way better imo and is far less messy. I've never had Dovah ingest any in the 8 months he's been on it.