I have the herculiner in my 87 Wrangler. It is a thin rubber type material, alot like rhino truck bed liner. It is really nice if you just want to hose out the inside of your jeep to wash it out. I noticed that the floor gets hotter because it is black and it is also noisier. I'm going to put carpet back in mine because I don't like the heat and noise. I don't ever get enough dirt inside to really make it worth while to just take the hose to it. Most carpets clean up rather easy by getting them wet and then using a vaccum. Depending on your use of your vehicle you might like it better than me.
1987 YJ, 4" lift, 33 x 12.5's, 4.2l
2001 TJ, 4" lift, 33 x 12.5's, 2.5l, air raid intake, air raid TBS