I have a black ( exterior) TR4 with a red interior and I used black carpets. They help to set off the red interior instead of washing the red out. I believe that red carpets would just be to much red. I also dislike what the red carpets look like when they fade a bit. The carpets seem to fade much faster than the rest of the interior pieces, including the seats.
There is my opinion.
Charley Fitch
