I have about 10 gallons of different cleaners.. MAAS is by far the best I have tried. The Westleys is pretty good on silver ... but I can go over a horn that has roughed up lacquer spots and the MASS is less obvious.
I then put some car wax on it. It protects the horn from retarnishing too ... and if you use a Meguires product it will have a very nice scent.
I do use Brasso.. if the finish is toast and really dirty ... then I go over it with MAAS.
I always tell anyone that is buying a horn from me that they need to put some polish on it once a month to keep it from tarnishing. I feel it's misleading to strip a horn and polish it up, knowing full well they are clueless as to what is down the road. If I lose a sale, so what, I have to be able to look at myself in the mirror each day.