The hole in the core of Joomla! (IMHO), even though it allows a "definition" of ML support, and even though it does give you more than one language for your site, as far as Joomla! and functionality is concerned, it might as well be viewed as multiple "forks" of the site identified as belonging to a language. It does not manage and associate between the various languages of your site. Great if you don't care about any synergy of the content between the languages, but I don't think most site builders want disjointed content between languages. If you wanted that, just build two sites!
Understand that the main reason for this extension is not to "translate" the content, but to "manage the associations" between the language versions of the content.
I have had the pleasure of working with the developer on some issues, and they really are serious about providing a tool to bridge the gap between Joomla's ML features and content translation management.
Great support, and once you get things set up and your head around the way the tool works, you will see nothing else fills the bill while maintaining standard Joomla! ML structure like this extension.
The latest (PRO) version has added abilities to track inconsistencies that could easily go un-noticed, causing many problems.
Many thanks to the developer and appreciation for the scope of what this extension accomplishes.