Someone near me has a Royal KHM that looks pretty clearly to be rebuilt -- overall grey finish, with no decals at all. Since the KHM is a really pretty machine in its gloss black finish, the dull gray crinkle is, well, dull. But these are fine machines, and I am very tempted.
While the typewriters may not look as great with the new finish as they did when new from the factory, a rebuilt machine has its own story. And, any process that brings the machine up to full working order and prolongs its life is a Good Thing. I realize, though, that for some collectors, only the original factory finish is acceptable.
