just say no to mineral, unless you don't mind a few scratches on your crystals.
i can't stand even microscratches on a crystal unless the watch is a class A beater....i.e., my g-shock.
here are my sport watches....
the seiko diver has a sapphlex crystal and is used as a work watch. there's not even a microscratch on the sapphlex crystal, which has worn like sapphire for me.
the tudur has a thick acrylic crystal that is easily buffed and the citizen is sapphire.