Re: Grand Seiko vs Swiss movements
I've got the JLC master control (calibre 899) and the GS SBGM029 (blue dial GMT, calibre 9S66).
Originally Posted by Crunchy
One important advantage of the Grand Seiko is the power reserve of 72h vs ~40h for the JLC. Both use single barrel mainsprings. The difference is in the proprietary SPRON alloy used in the GS mainspring.
My JLC master control uses a free sprung variable inertia balance wheel. Compared to a regulated balance wheel, this has better stability of rate and inherent positional accuracy. I don't know what type of balance wheel my GS uses.
I don't test my watches' accuracy but both seem equivalent to me.
'I reach for my watch from the bedside table and consider the dial - its rectitude, its innocence - then I understand the position of the hands and that, yes, rush-hour traffic will already have begun.' - Deborah Eisenberg, The Flaw in the Design