Ranked in these QuestionsQuestion Ranking
Pro Good fuzzy completion
Pro Clang code completion
Pro Multiple ways to complete. Multi language support.
Con Too many dependencies
Compared to others, it has too many dependencies.
Con Only C family languages
YouCompleteMe works best for C-based languages (C, C++, Objective-C, Objective-C++) and it's semantic engine is Clang-based which means that it only works for the C-family languages.