The primary advantage is that Sam and the dev team get important information from users who have some competence in testing software and providing meaningful and actionable information so that outstanding usability issues may be found and resolved. Such is the path toward ultimately making the testing builds the stable, widely disseminated version. The current testing builds simply do not have the 3d function cooked in at the moment. Things have to be prioritized.
Secondarily, if you wish to continue discussing in this direction, please create a new thread so the focus here can remain on point.