I used to be a SuperMemo user for several years and accumulated more than six thousands items. It has advanced algorithms. Both Anki and Mnemosyne are based on the algorithm of SuperMemo 2(its version is 16 now). And there are several pieces of articles about human memory on its website which are very helpful.
But about a year ago, I gave up Supermemo. Because it's really buggy and bloated. I was so worried about my data that I used to back up my data into a zip file every day. Then I decided that I shouldn't trust a buggy closed source software like SuperMemo to protect my data. If it died, I would have trouble converting my data to other formats.
When I was considering the alternatives, I chose Mnemosyne instead of Anki. Because Mnemosyne seems cleaner, and its author is doing some research on human memory which made me think that its algorithm could be better than Anki.
Unfortunately there's no sign of progress on the Mnemosyne research project, it looks unlikely to ever happen at this point. It uses the same algorithm as Anki (SM-2) as its base. Not to say they are equivalent though - both (especially Anki) add many refinements to the basic algorithm.
But about a year ago, I gave up Supermemo. Because it's really buggy and bloated. I was so worried about my data that I used to back up my data into a zip file every day. Then I decided that I shouldn't trust a buggy closed source software like SuperMemo to protect my data. If it died, I would have trouble converting my data to other formats.
When I was considering the alternatives, I chose Mnemosyne instead of Anki. Because Mnemosyne seems cleaner, and its author is doing some research on human memory which made me think that its algorithm could be better than Anki.