I'm still not sure about all this running in stuff. I own 10 watches, nine were bought new. Some have slowed down marginally over a few months, others haven't changed at all. I regulated all of them within a week or so , apart from two which didn't need it. If all the bearings are running as free as possible and there isn't excessive lubricant affecting rate I don't see the slowing down syndrome should be significant. I imagine that a movement built with more care and to closer tolerances would stay more consistent than a crudely finished one. However, my Russian Vostok Europe watch, after regulation, is my MOST accurate mechanical watch, within a second a day or so. Consensus
seems to suggest that Russian quality control is very poor, but as my Vostok is so accurate, I don't know what to say?
Cheers,
Martin