I build my own when shipping 8000's and such. I use nice quality plywood and the bass cabinets are suspended in the crates from the top and bottom so that the sides never come in contact with anything. The heads are shipped in an additional crate together. Once all of it is strapped to a pallet, it is very secure. Takes a little time but costs less than 300 in materials. Best of all it breaks down flat for easy storage and reuse and won't deteriorate like cardboard.