Bare aluminum scratches too easily, and a machined surface can't really be repaired. If it has a brushed look like the other bare aluminum parts on the bike, scratches are easy to fix with red Scotch Brite (deeper scratches may require 400 grit first).I vote silver. Show that beautiful CNC work.
The reservoir is in the main case below the supercharger built in. You can see the filler neck at the back. The filter is just a magnetic sump plug at the bottom of the res. The front of the main case is finned and the belt guard has 3 louvres along the outer vertical edge to catch air and direct it over the fins and disperse through a slot on the inner edge and around the vents you can see on the outside and top of the supercharger. The res holds a lot of oil so I am hoping it will keep cool enough. If not we have ideas on a cooler.Richard... you tease!.
Where are the oil reservoir, filter, and cooler on this one?