I love seeing the Japanese lists for tournaments. It's because of them that we got Sylveon control looking the way it did initially.
That said, we have to take these lists with a grain fo salt when it comes to application. Obligatory "They are XY-on and we're not" yadda, yadda, yadda.
At the very list, this can be directly applied to Expanded with the addition of an Ace Spec and whatnot. Otherwise, this sort of thing should only be considered if someone is going to Worlds. Even then, they have Shaymin-EX and VS Seeker., Hex Maniac, and Battle Compressor available to them.
Outside of worlds, post-rotation, I think the deck will be too slow to operate. I know VikaRay is a decktype that gets thrown around. There is SOME merit to it, but Rayquaza-GX makes the deck clunky and slow and you need an absolutely PERFECT hand to do 210 on T2, where VikaBulu doesn't require AS much setup for 210 T2 and can do it consistently.
Rayquaza does not loose that much from rotation. The main reason Rayquaza is that good is Latias Prism Star. This card provides nuts acceleration with three Rayquaza GX on the bench in addition to Rayquaza's own Storm and Stress.