Unless you can find them on ebay, which actually isn't that rare, I would go with Weather Tech. Ebay almost ALWAYS has carpets and mats on auction for many cars, sometimes even new, for about 1/5-1/4 the price from the dealer.

I recently got these mats from Weather Tech for my Maxima that are lined with rubber, but have a carpet top. So they feel like you have carpets in there, but hold a quart and a half of water. They are a bit on the expensive side, but fit very well, feel and look like carpet, but hold 1.5 quarts of water.

You can check out their stuff at:

http://www.macneil.com/