The cleaning/restoring of anything "old" is a very subjective matter. Remember, once you do something to it, it's usually impossible to "undo" what you have done. If you definitely want it to appear as if it were new, then go ahead and use any of the myriad of silver cleaning methods (including washing soda and aluminum foil). Things are like people, and as they get older they develop character marks that show their age, and these "flaws" are part of their history so why get rid of them? As woofgang mentions, once you remove that, sometimes very attractive, patina of age you aint getting it back for a long time. Have I answered your question? No, because it's entirely up to you to decide what to do.