I prefer to use sandpaper to restore the finish. I use the black, wet and dry sandpaper (I use it dry) and Ihave it in grits of 850, 1000, 1500 and 2000. Depending on the agressiveness of the existing finish one of those grits will generally match. I normally would start with 1000 and then work up or down if it is not aggressive/too aggresive enough. Again follow the grain exactly. Sometimes you are more successful holding the sandpaper steady and just moving the bracelet or case in a very exacting movement. Try and go over a whole section at once rather than just focussing on just where the scratch is. All my brushed finished watches look new
Hope that helps