Due to the announcement made here: http://scripting.com/2016/08/24/fargoTimesOutOnJune2017.html
about the changes Dropbox is making that when implemented will break Fargo, I've been thinking of/planning the movement of my OPML data to Little Outliner.
One big difference between the two is encryption. Fargo has a feature that supports encrypting an outline, Little Outliner does not. I've used this feature lightly, and I only have one important file in which I use encryption, but the key point I think is that it will be really important that if anyone is using encryption in Fargo that they decrypt them before the expected 2017 date otherwise I think they will lose the ability to read the files in any way.
If it were possible, I would like to make a feature request to port the encryption functionality in Fargo to Little Outliner. Encryption and the Add feed functions of Fargo that are not in Little Outliner that I will miss.