Thanks @Aidil and @Outbush for the responses.
As a side note, Gotoh's product specs are
very confusing for the GB series tuners! I've searched their most recent catalogs and have found differing weights for the GB350: 31.3g (
TBer even received info from a Gotoh dealer) and 40g (
TBer even received info from a Gotoh dealer). The same goes for the GB707 which ranged between 60g to 64.4g; and one
Invalid Link Removed stating 68.5g for the GB707 and 64.4g for the GB720 [discontinued], instead. So confusing! Four grams of a difference between the 707 and 720 should not be enough to warrant calling the 720 "lightweight."
My best guess is that GB707 are the heaviest at 64.4g; the GB720, having an aluminum shaft and plastic button, are in actuality probably 40g; and, based on the newest catalog, the GB350 with aluminum gear, worm, and shaft, as well as plastic button, would be 31.3g. These weights would seem to make the
most sense to me since, then, the GB720 would indeed be much lighter than GB707; 8.7g heavier than GB350, yet still lighter than Hipshots (~42g). Costing only a fraction more than the GB707, I would make sense for Gotoh to discontinue them.
Sorry for pedantic rant