I cleaned my drivers seat today(the other seats are in perfect condition) and was very happy with the results. I would have taken a before and after shot of the seat but I wasn't expecting it to come out as good as it did. Instead, I attached a during and after shot. The stuff I used is a leather cleaner/conditioner made by Weiman and I used a soft bristle toothbrush to scrub. It took almost two hours but my seat was really dirty.
This pic shows the cleaned right half of the perforated section of the seat
This is the final result:
This pic shows the cleaned right half of the perforated section of the seat
This is the final result: