Does anyone have any preference on Eyelash extension companies (i.e., courses) ?  I am ready to take an extension course(s)  but new companies are popping up constantly.  It does seems to be a popular opinion that the 'mink' lashes are the most comfortable for clients... but does anyone have any experience good or bad with any of the more well know companies ( Extreme, Lash Out, Nova, Lavish, Extend Your Lashes).   Thanks, Sharie