I found that if I kept a bag of clean media for end, and used that for the last 10-15 minutes (eg swap out and keep the dirtier, and replace with clean), then I got a nice shine on it..
I usually start out with the dirty, and add a bit of polish to it (which cleans the brass a lot, but gets the media really dirty so you don't get the really good shine.).. then once it's cleaned (but not shine) I change to the clean media, and it puts a nice shine on it.