I like the UI, but the software just didn't work. I loaded two bibtex files, merged them, removed a few duplicate entries and then saved the merge. When I tried to use it, at least a dozen of the entries from one file were missing completely. I tried the merge again without removing any duplicates and the same entries were still missing. I like that this isn't as bloated as JabRef, but unfortunately I can't use it as it is.