You'll be amazed at how much it will shine and the depth once you thoroughly clean it and hit it with iron remover. The amount of rail dust that was on mine pretty much told me that is sat in a rail yard for multiple weeks. Then it was time for polishing and the original protectant was Paint Sealant. The Spray Wax works very well and in the Texas sun, you'll need to apply the Spray Wax about once a month.
Long term, I'd have to recommend the Graphene Spray Coating, it does an amazing job and makes it much easier to keep clean.