Which LMS do you use and why?

We are in trials now to select a replacement for our current and overly robust LMS.  I chose the most user friendly for my short list and focused on funtions that are most important to us.  Seems they all can deliver content to users equally well so I 'm concentrating more on how well they perform and, most of all, how easy they are to use on the admin side.  The ones I chose for trials had either very basic authoring or none at all.  I decided to search separately for a GOOD authoring tool knowing that most LMS's can handle scorm content.