one of my favorite making-of is "ONE DROP" where Kame is all like, "OH DAMN I FORGOT WE'RE SHOOTING THE MAKING-OF".

and the "tennis" scene. i also loved the making-of "SIGNAL" too (but the DVD didnt have the PV, WTF! xD)
speaking of the BTR DVD, i saw the LE Disc 3 subbed on YouTube...it was really insightful, imho. about how KAT-TUN works. i love how each tour has a specific theme and they bring back an element or 2 from previous ones. i think you also understand group dynamics as well. seperate, but together!
btw, KAT-TUN will sing both THE D-MOTION/Love yourself on MUSIC STATION next week! weirdly enough, the Backstreet Boys will be there also. both fandoms colliding, i love it!