They may be quite clean when it comes to assembling watches, but I can't say the same about their battery replacement procedures. About a year ago when I sent my D1 watch in after it battery gave out, it came back with a few noticeable bits of dirt/dust that would move around under the glass. I will say I didn't baby the watch in the least, using it at times when I knew it would take a beating. Maybe I had an isolated incident, but the whole thing left me irritated. Although, it's not something that even came close to preventing me from getting another Oakley watch.