I've tried finer papers but now never use anything finer than CAMI 600 on
baffles and exteriors. This is the same a FEPA P1200 or 15 micron.
http://www.jamarco.com/91b_Technical/sandpaper/Making%20Sense%20of%20Sandpaper%2\
0-%20Page%202%20-%20Fine%20Woodworking.htm
I then use "0000" stainless steel which gives a fine but non-gloss finish. I
stop there most of the time. If I want a gloss finish is use some polishing
compound by hand and then some Flitz again by hand. It is too easy to do damage
with power buffing IMO.