What bike is it for?
One of those 2 wheeled Mercedes 190e's :P
I've read that hard anodising is not advisable on floating discs, as it can break off due to the constant rubbing, and then you're left with excessive clearance.
I'm undecided on whether I go for solid mounted or floating, it depends on whether it's cheaper to have bells made by someone vs buying a bespoke kit.
@Seadog something like this.
Left is fixed, right is floating.