Never been to Cuba for the purpose of buying cigars so cant comment there, however, the most consistent vendor I’ve purchased from blindly is in HK. All other markets have been hit or miss when buying blind. Mind you this is one particular vendor, I’ve purchased from other vendors in HK and received some less than desirable boxes. Also in general, Singals from most vendors seems to be of lower quality, ime.
That is why I almost exclusively buy from 24:24 now, no more blind folds.