When comparing YouCompleteMe vs Neocomplete, the Slant community recommends Neocomplete for most people. In the question“What are the best plugins for programming/scripting in VIM?” Neocomplete is ranked 1st while YouCompleteMe is ranked 3rd. The most important reason people chose Neocomplete is:
Noecomplete's author has made some very good plugins which are also actively maintained.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Good fuzzy completion
Pro Multiple ways to complete, multi language support
Pro Clang code completion
Pro Works out-of-the box, not much configuration work necessary
Maybe use this:
let g:ycm_add_preview_to_completeopt = 1
let g:ycm_autoclose_preview_window_after_completion = 1
nnoremap <leader>d :YcmCompleter GetDoc<CR>
nnoremap <leader>j :YcmCompleter GoTo<CR>
Pro Good plugins
Noecomplete's author has made some very good plugins which are also actively maintained.
Cons
Con Too many dependencies
Compared to others, it has too many dependencies.
Con Extremely heavyweight
YouCompleteMe installations are hundreds of megabytes large.
Con Works best only with 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.
Con Does not have function arguments quick-preview (for Python)
You need to check the Docs too see how a function is defined.
Con No Julia support
Only Deoplete seems to have that at the moment.
Con Active development has stopped
Neocomplete is no longer under active development. It's considered deprecated in favor of Deoplete, the newer and async version.
Con Neocomplete does not work with all Vim versions
It requires Lua support and the Lua driver.
Con No support for Julia
There's none to be found.
Con Autocompletion can be slow
Some users have reported that Neocomplete's autocompletion can be slower than other alternatives.