I use Obsidian Stem Oil on my vulcanite, as I tend to smoke in the elements a fair amount. I've found that with Obsidian, my stems don't discolour in the sun, nor do I end up with "polka-dots" of discolouration if I venture out into the rain; both of which I can't say about the EVOO. If I come across ugly acrylic, I use a product called Nomex Scratch Remove (Grade 2) that I buy from an acrylic fab shop in my neighbourhood.
When it comes to removing oxidization on stems, I use toothpaste (if it's not too deep) or micromesh pads (if its deep). If I need to clean the outside of a bowl, I use a toothbrush and elbow grease...and a little alcohol if I am not too worried about the stain.
I use Claphams Salad Bowl Wax (beeswax/carnuba/micro-crystaline mix) on my briar, and plain beeswax on my meer. Both can be found through Lee Valley Hardware.