I am using vim with the LaTeX-suite for writing longer texts. But I had one problem when using the \cite-completion with F9. Instead of getting one split-view with nicely formatted entries of my bib-file, I got two split-views: one with cite-keys, one with my unformatted bib-file. I could go through the cite-keys and the bib-file would jump to the right entry but that’s it. Nothing to see of functions like filtering etc.
The solution was to install vim-latex manually. I am using normally NeoBundle and used previously vundle for managing my plug-ins. But those seem to interfer with the functionality of vim-latex. So, if you run into the same problem, just de-install it with your package-manager and install it manually from Sourceforge. It is cumbersome but it works and the plug-in got updated the last time over a year ago, so missing out on updates do not seem to be that much of an issue.
P.s.: Another problem I found when googling many people seem to have is, that the cite-autocompletion won’t work when there is a space in the path to the bib-file or when there is for example a leading space in bib-entries like “@article{⎵kobschaetzkix2014gh, …”