Personally, I err on the side of caution when it comes to all weather mats. To me they are function over form. I'd love for them to be a nice deep clean black, but also won't risk anything that could potentially make the bottom of my shoes slick which could cause an accident. I know many protectants these days offer a matte/satin finish, but I still feel some slickness in those products after drying. So for me, I just leave them au natural. Just my opinion though.
So far, the best cleaner I have used that left a decent finish was ARO. Typical APC's I have used have left a duller finish.