I can't speak for Dexters, but Linds recommends a mild dishwashing detergent and a soft bristle brush for cleaning their soles....just be sure to rinse all of the detergent residue out of the leather and allow the leather to air dry (no heat) in front of a fan.  However, Dexter may recommend something different.

As for cleaning the heels, I can tell you from experience that I leave the glassy buildup on my Linds heels. I tried cleaning the buildup off of the heels once, and although it wasn't difficult to do, it turned the heel into a HARD braking heel....it took a couple of games to get the heel toned down again to the point where the braking was predictable and smooth.  Again, Dexter may have a different idea.

I use a wire brush, and every now and then, when they get really dirty, I take some burgundy scotch-brite pads and use them on the soles and heels.