The hard shell seat and the temporary seat with padding.
I rented the temporary seats for one game and ended up giving mine away. The problem with the padded rented seats you carry to your bleacher is that they are 3" shallower than the bench itself, so you end up sort of perching on it rather than sitting. I need that 3" of depth on the bleacher, it was too uncomfortable to give that up and have my knees in the back of the guy in front of me. The guy behind me LOVED it. If you're small in stature they seem to work well, my wife enjoyed using hers.