I only have 2 Leo's but if I had a rack with lots of reptiles I would use high end stick on tiles (the nice ones dont give off gas at that heat) or paper towels. Slate can be a pain if your using sand to level, unless you can find really even slate shingles or something. It really depends on what you are looking for. Easy cleaning? Or nice look? Stick on tiles are a very nice option for tubs though
I use tan shelf liner...Its very easy to wipe off..Doesn't get ruined when water gets dumped over....I was going through wayyy to many paper towels..
I just redid my tanks in slate tile, so far I like it