hi KK,
just to share more info on SD..(my hands on SD experience goes as far back as pre-2010 with my SBGC003 which is one of my regular office watch)
Spring Drive's average accuracy (meaning from 1 SD to another) is AFAIK < +1 to 2 secs per week (although GS sets a much lower claim of < +1/day i.e. <+7 per week)
Fellow mwf owners e.g. david, sean, euclidorus who own SDs can testify to that...
V v few mechanicals can come close, not to mention equal.
Even though there are reports that those v v few mechanical watches can achieve +1-2 secs after a week, its because of +/- compensation from day to day or due to compensated positional accuracy (i.e. due to different resting positions throughout the day/week)
The Spring Drive OTOH is consistently accurate i.e. you can check on a hourly/daily basis. There is no variation in rate regardless of position, shock, temperature. I've spent a lot of time checking out the SDs against super quartz and atomic clocks.
Apart from the SDs, I'm lucky to have a few other mechanicals that can achieve < +1 to 2 secs/day (not per week) e.g. Nomos, Damasko, etc
Thanks kclee66, jeepWH n watzisname,
Precision is good for a 40+ year old. Have not really check cos I rotate a lot. But keeping good time but kalah to your spring drive, Joseph.! . Most of glashutte info is from our dear uncle Google. .. n forums like WUS ..