A.C.
I'm a fan of FLOR carpet tiles. In particular, the House Pet line for heavy traffic areas. They look good, have a heavy rubber backing and don't show all the water and grit that comes through our back door. Easy to install and the colors are beautiful. But according to the website, they are not recommended for heated floors. Good luck!
http://www.flor.com/house-pet-hummingbird.html