Yes, KAT-TUN concerts are grand. The Concert, people are raving about is called Break the Records, like the corresponding album.
It's for breaking the record of having the most concerts in Tokyo Dome (10, 8 consecutive) and KAT-TUN themselves were very involved in the production. They had a planet theme, and every night another member was responsible. Imagine what fun it is to watch such a concert, if you actually like the band. (Like I do with KAT-TUN) They were touring Domes, even before debut, so they got a lot of practice.
I would slowly build it up and watch the concerts in chronological order, though. Much more fun!