Mmm tricky one. ive been pondering the same question myself. An AD told me the sub will prob hold its value a bit more than the gmt, but my Franken is so close it sort of feels hard to justify the cost of a gen sub.
Also the gmt has the extra feature of the gmt hand, and as we all know there is no good replica of this movement, so although it will look close, a rep/Franken gmt will never properly replicate the function of a gen. Whereas a good rep or Franken sub will look and function exactly the same as a gen.
I'd also say though go and try both on at the same time. Go for the one that sings to you most!
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