Huh? 4X4s come with carpet floor mats??? Why in the world would a manufacturer put carpets into a 4X4?? Bling for posers?
Rip them out and replace them with removable rubber mats so you can hose them and the floor down to get the caked on mud or sand out. I don't think the brand matters so much as long as you can remove them, hose them down & put them back in.
For the Land Rover crowd, I think Exmoor trim makes the best rubber mats. For Series trucks their mats are much superior to the factory rubber mats.