What site are you looking at? I will be adding some next year, and was gonna go with the new carbon fiber style. They are bigger, trimable, and put out a more even heat without hot spots. I have not looked at price because I will probably get them regardless what they cost, it's in my head now. Here's the link if interested. They do the leather seats for Roush, Saleen, Shelby etc, so it may even be the same elements used in those factory seats.
http://roadwire.com/products3.html