I took my Casio Sea Pathfinder Watch to the closest Bureau of Meteorology 3 days after I got it. (South Australian Government Dept.)
I wasn't worried about the temp because I dont use it that much, but the Barometer was spot on with their measurements.
I hung around for a while for a chat and to let the watch settle for a while to make sure.
Now its the refference to adjust all my friends barometers.