Which LMS do you use and why?

My previous employer user SumTotal, firstly TotalLMS and then later the newly launched Learn Enterprise.  I actually really like this system in terms of how configurable it was and how much of this configuration we were able to do ourselves without having to go back to our vendor to make changes every time.  I will say that creating library items in the system was a little fiddly and sometimes the structure (in terms of employees and reporting lines) was a little complicated but on the whole from a user perspective it was quite easy to use and navigate and their support desk were pretty great with assisting us too in a timely manner.

My current employer users LearningSeat.  It's very different to SumTotal in that there isn't much configuration we can do ourselves, we need to go back to our vendor almost every single time we need a change made.  Also there isn't a viewable structure in the system, you can link other users as managers but you cannot create a structure at all which can make things a bit messy.  I do find their support desk isn't very quick with responding and when I pick up bugs which they send to their developer, a month can go past without communication and I often have to follow them up rather than getting regular updates which is also quite annoying.  That being said, from a user perspective it is extremely easy to use and intuitive, creating library items is extremely quick and easy (it took 5-10 minutes to set up an ELearning in SumTotal but about 30 seconds in LearningSeat as there is a wizard and you don't have to manually change many settings).

Both systems work perfectly with Articulate (both Studio and Storyline) and both have really good reporting functions although again, LearningSeat's reporting function is probably more user friendly.

Happy to answer questions on either if there are any!