Mine is mostly for looks, as it is really quite a problem child. But there's just nothing like the look of acrylic on a Submariner. (rest assured, I only paid a 'problem child' price for this particular 5513) All of the important external bits are service replacements: bezel insert, dial, hands. Not sure about the crown. It has been polished, probably too much, and brushed, probably too much. Believe it or not, this 5513 came out of the factory in 1964. Inside beats a Cal. 1530 movement -- which Rolex eventually realized was design (and cost) overkill for a non-certified movement. "Beats" might not be the best description of how this movement works -- "lurches" or "chugs" might be a better description, at a sloth-like 2.5Hz/18,000vph. But it is MY problem child, and I do love it