I have worked extensivly with Moodle, Docebo, Ed, SumTotal, Saba, built my own "poor mans" LMS, and modified or worked with about 7 or 8 other unmentionables.
In every case below, I've customized the LMS's at the code level and can say the following:
Free systems:
Moodle: Great software architecture, very scalable, supports many languages, can be modified at the code level bloated as heck, terrible work-flows (although you can create your own work flows) for users and worse for admins.
Docebo: Clean and simple software architecure, great user workflows - that you can customize totally, very easy to customize (via code, or just admin configuration) and you can edit in all 32 languages, create custom client portals with their own work flows, courses, catalogues, etc..., not recommended to 100+ simultanious accesses.
Paid:
Ed: Amazing LMS, do anything with anything, supports any SCORM, and AICC, incredible dashboard, supports Certifications, skills, competencies, production planning, feature rich like no other, very like and intuitive work flows, extremely expensive (like 150,000+ to get started with your own server, or about 10.00 / month per active user for hosted) - This system was originally designed for aerospace manufacturing.
SumTotal, far too expensive, user work flows are terrible (example: My Completed Courses is a collapsed (hidden) areas below My courses (rather than a tab t the left where all other user page navigation is), Admin functions are divided into 4 round buttons accross the header, after you select one, you get to guess which of the 5 menus below you need to use to do a task, and the pain goes on...
Saba, got 150,000.00 so they can send their expert to answer your questions, then give you the product to install, next, you still have to pay them per user when you exceed teh number that the original cost covered, btw - you are not allowed to customize it at code level - oops, been there - done it, not goin' thar agin'
My own LMS: Absolute failure compaired to all of the above (although I ran simulators off it which no one is yet doing today), also not available anymore 
I hope this information can be of help.
Best Regards,
Dennis Hall
