I received P90X last June and completed the 90 day classic rotation exactly as is (no substitutions) in September. I LOVE these workouts! In fact, I haven't been able to give them up to this day. I loved increasing my pushup and pullup ability, being able to increase my weights every week or two, increasing my core stength (and hip flexor strength!) with abripperX. The leg workout wasn't as heavy duty as Cathy's, but I loved not having to use weights for most exercises.
After my rotation ended, I continued to use Chest & Back, Ab RipperX, and Legs & Back mixed in with Cathe cardio and weight workouts. I modified Legs & Back into an awesome purely legs workout by substituting heavy weighted squats, walking lunges, and either heavy weighted deadlifts or hamstring rollins on the ball for the 8 sets of pullups. I never fail to get doms from this workout. I also love the functional exercises, the balance challenges, and the way almost all of the leg muscles are worked so well. I have ocasionally thrown in a Cathe leg workout, including GS Legs, and none of them challenge me as much or give me doms.
I still can't give up these workouts, but wanted to start doing Cathe's S&H, so I'm now doing a rotation mixing in both.
So, I guess the answer to your question is YES! I would still get these in a second!
All the best!
Randi