The concert can be said to be of the same scale as "Soul G - Music Dedicated to the Warriors" held in October last year. Unfortunately for us, there isn't much coverage on this event for international fans to know how it went, except for this report from Gundam Dot Info.
The concert started with "Resolution", the second opening theme from "After War Gundam X", performed by Masaaki Endoh (遠藤正明). This is followed by various classic Gundam anime songs performed by the songs' original singers and other new singers. The crowd was electrified by the performance.
Image and information is from Gundam Dot Info.