While Mendeley (particularly the desktop application) is quite good as a reference management system, it does have its limitations. You should be aware of the following shortcomings:
Citation Import Problems: Mendeley Web currently will NOT import citation files from the following databases (these do work fine with Mendeley Desktop, however).
Mendeley Importer Extension (Google Chrome) - This Google Chrome extension interferes with ProQuest eBook Central, causing eBook pages to load and reload continuously, making interaction with the book difficult if not impossible.
Range of document types: Mendeley has a relatively limited range of document types, compared to other reference management softwares (EndNote, RefWorks, Zotero).
Mac Users who have OS Sierra and High Sierra may need to download an older version of Mendeley (version 1.16.3 - see here https://www.mendeley.com/autoupdates/installers/1.16.3) for it to work on your machines.