Within the world of vintage watches, Grand Seiko – distinguished by the “GS” on dial/crown and gold medallion on its caseback, like this full-serviced 1969 Grand Seiko 6145-8000 Hi-Beat dress watch automatic here – inhabits the top of the food chain, simple as that. 
 
Grand Seiko – with 51 different models – were simply the most painstakingly designed and exquisite watches made by Seiko, produced by both the Dani and Suwa factories.
 
The 61GS Hi-Beat series started production in 1967, full of Grammar of Design awesomeness, with sales continuing through until the end of the vintage Grand Seiko era in 1975, when it became a self-inflicted fatality of the quartz crisis.  The high-beat credentials of the 61GS are entirely authentic in that these movements run at 36000 beats per hour or, to put it another way, 10 beats per second or 5 Hz.
 
The 61GS was the second generation of Grand Seiko automatic, following the rather short-lived 62GS that dominated from 1966/1967 to circa 1968 (the 62GS was preceded by the Seikomatic 62 Chronometers in 1966 that were identical in all but branding).
 
Speaking of Grand Seiko design, in the early 1960s, Seiko’s Tanaka created a set of design principles he called The Grammar of Design.  In 1962, Tanaka noticed Swiss watches "sparkled brilliantly" and realized the design of high-end Seiko watches could be radically improved through the implementation of "flat and conical surfaces perfectly smooth and free of distortion."
 
Tanaka’s Grammar of Design made the Grand and King Seiko lines instantly recognizable as status symbols in the hierarchical Japanese business world of the 1960s and 1970s.  Tanaka’s rules would go on to fundamentally change Seiko’s design language.  All surfaces and angles of the case, dial, indices and hands had to be flat and geometrically perfect to best reflect light.
 
Following this aesthetic, bezels were to be simple two-dimensional faceted curves.  And third, no visual distortion from any angle was allowed, and all cases and dials had to be mirror-finished.  In “A Journey in Time: The Remarkable Story of Seiko,” Tanaka’s approach to the new style is described as follows:

“He started by creating cases and dials that had a perfectly flat surface, with two-dimensional curves on the bezel as a secondary feature.  Three-dimensional curves were not used, as a general rule.  He also decided that all distortion should be eliminated from the dial, too, so that it could be finished with a mirror surface.  This formed the basis for the new Seiko style.”
 
For a brief period in the late 1960’s and early 1970’s, some Seiko’s were certified chronometers by Bureaux officiels de contrôle de la marche des montres (precursor to COSC).  Seiko's history with the Swiss official chronometer rating is an interesting one, from Seiko's first participation in 1963 to its entry of the 45 calibre in 1968.
 
Seiko nearly always placed rather well vis-a-vis its Swiss competition - almost certainly to the embarrassment of the Swiss.  When the successor to the chronometer contest was established, the COSC standard, the Swiss made the odd decision that "all parts used to build the movement must be made within Europe” ... jealous much?
 
Seiko would eventually eschew the Swiss-based chronometer certification in favor of their own, more stringent, standard, thusly beating the Swiss at their own game.  And Seiko would go on to be the first to invent the automatic chronograph and then the world's first quartz movements (beating the Swiss, again, both times)...but those are stories for another time.
 
Make no mistake, Grand Seiko then and now marks the very best Seiko has to offer, easily on par with the vast majority of what Switzerland has to offer by way of competition.  And the Grand Seiko 43999 SD represents one of the highest achievements of Grand Seiko – namely, creating one of the best watches on the planet.  Period.
 
This Grand Seiko comes on a leather strap, and with nylon strap, rugged travel case, and springbar tool.