When contemplating strap modifications, understand that Grand Seiko straps might not match as effectively. I’ve a GS myself and regardless of the very best match I may get, the watch typically stays somewhat looser than I would love. I’ve learn instances of people that finally bought their GS as a result of they actually wished to put on it on a bracelet however could not discover a super match.
That being stated, I might go for the much less cluttered look of the SBGP013 until you propose to make use of the GMT operate (or simply actually need the look).