WATCH POP

As I know when you send the watch back to the factory for repair Lange will polished the watch for you for free, which is good. But I have a bad experience with a very famous brand, when I send the watch for polish the watch came back I can tell the difference. the shape of the case very slightly change a very little bit. ( if you pay attention to it.
is this happpen because just bad example that happen to me OR it's going to be a little difference no matter who does the job?
Also I heard all those very exensive vintage watch which fetch high price on the auction they never been polished. even you can tell many tiny scratch on the watch. Polish lower the value of the watch. Is it true?
I am going to send my watch to Lange to repair my moon phase, since it is brand new Do you guys think I should request them not to polish the watch???
any comment is appreciate.
Mr. Chong will you give us some thought ? 
thanks 
and the work was done at the factory, on a platinum case. I don't know how I managed to scratch the case, but I did...and they polished it out...I am very satisfied with the work. 
Having said that, I must remind that the act of polishing involves removal of metal to the case. And if the polishing is "heavy" enough to remove deep scratches, it may be likely to slightly change the shape of the case. I would recommend no polishing unless the scratch or mark is particularly significant or deep. I rather prefer the look of a lightly scratched case...developing a beautiful patina, rather than a brand new shiney one.