The shield does not conatact the metal on the filter, it actually sits on the rubber mount, away from the functional area.
I agree, the whole filter should be covered, indeed to incorporate the intake, this would, in my opinion, look crap.
I do like aesthetics, perhaps even more than performance, this is a compromise.
Anyhow, I'm going to add a clear perspex shroud to the alloy ring, this should allow more trapped air, and let you see what's under it.
Gary
