I suspect I have several instances of duplicated files on my hard drive and I want to get a duplicate finder app to help me track them down. Gemini (by MacPaw) and Twins (by Rocky Sand Studio) seem to be the most popular duplicate finders on the Mac App store. Unfortunately, neither has a trial version. Can anyone comment on the quality of these apps? I'm particularly interested to hear from anyone who has tried both. Also, are there any other similar apps worth considering? I realise that these apps are unlikely to be perfect at finding duplicates, but given their low prices, I'd be happy if they are only moderately helpful.