Of all those I've tried, I liked the 1/4" corrugated (it's like regular corrugated cardboard with one facing removed), especially for heavy bodied or "pushy" snakes.
Good to have options though...and if you want the "greenest" option, it's indoor-outdoor nylon carpet, cut to fit...but ya gotta wash it. That's the cheapest in the
long run, & makes the least waste, with good absorption, traction & excellent appearance. (it can be disinfected, even with bleach, with no color loss...the stuff
wears forever! Can also be shaken out to remove most of the water & put in damp, for added humidity, but it dries fast too.)
Interesting.
Never thought about bout the nylon carpet as I figured it would be too much of a pain to completely remove every time. I do like the "go green" idea though.