Just walk along the main shopping street - and do your own research.
The main thing is to watch out for counterfeit. Also - do not trust the "port shopping program" speeches.
Those stores may be "recommended" by the cruise line, but if you have any problems and want a refund don't expect them to help you. All you will get is lip service.
I am the editor, but I also speculate, ask questions and play devil's advocate. I reserve the right to change my mind.