From the BARKS English site, a translation of Shinji’s comment from the COLLABO BANG site:
I was first introduced to GRANRODEO through their videos. When I first saw them live, I fell in love with KISHOW-san’s vocals and e-ZUKA-san’s masterful playing. I wanted to do something with them in one way or another! I’m very happy for this collaboration! Here’s hoping it will be a wonderful night…
Also per the site, the show, at the Budokan, and also featuring DAIGO, TOTALFAT and LINDBERGH, sold out on the first day of the general sale!