This thread is a bit old but I have to say I have a ZF BB GMT since 3 weeks and I really like it. Solid solid watch for the bucks, everything is damn near perfect except 3 points which are minors and to be taken into consideration along with the pricetag (~$300 vs $4500 for the gen):
-ICHS -> inherent to the reliable movement presents in this replica (2836-2/ Asian take on the ETA with an added GMT complication, very reliable as documented in this forum, rep has been out for over 5 years and majority of owners seem to be still happy with it).
-Index/Dial alignement -> Simple QC issue known and well documented from ZF, just make sure to be okay with the fact it's almost impossible to get a fully aligned rep of this watch. Nevertheless, I've saw plenty of people complaing about GEN Tudor alignements...
-Asian ETA -> Ticking sound which is definitely different than the GEN in house caliber, it's louder and power reserve is subpar.
Everything else, like color matching of the bezel, texture of the dial, crispiness of the priting, bezel action, bracelet clasp/fit and finish, is damn near
spot on and it's shocking for the price.
Buy and enjoy with confidence, it's also a very good way to "try on" the watch proportions and overall vibe before a $4500 mistake