The only dressing I have found so far to give me a totally factory look to my dashboard is Poorboys Natural Look. Its not the easist to apply as its fairly thick, but on a damp MF it works easier. Everything else I have tried has added some sheen or gloss including 303. Due to the NL not being super easier to apply I do that once a month and mantaion with either 1Z Cockpit premium or Megs Interior Quick Detailer for weekly clean ups, as both give a totally factory matte finish with no gloss. So far 6 months on with the above interior looks as it did from the factory.
Gummi Pflege on door seals too, great product.
Plan to try the Opt Protectant soon, does this leave a totally natural, factory, matte finish?