The studio that's featured in the GREAT AMBITIOUS -Single Version- PV is Sangenjaya Studio which's owned by Sound Studio Noah Sangenjaya .
http://sancha.studionoah.jp/
Both Barks & Vif-Music mentioned that the guys used to jam together at Sangenjaya Studio before they made their offical debut as BREAKERZ in 2007 .
https://www.barks.jp/news/?id=1000152092
http://sancha.studionoah.jp/