I have only ever worn mechanical (mainly automatic -winding) watches. I have become accustomed to whatever watch I am wearing to be accurate within about 5 minutes per month. I am totally good with that. Recently, I bought a brand new Patek Philippe 5320g from an Authorized Dealer here in Beverly Hills. This watch is of course made with all of the modern ( mechanical) technology available. I took delivery of this watch in late March of this year. So far it’s accurate to within about 40 seconds per month! For me, that’s a BIG DEAL!!! (It’s a really nice watch by the way).