Oooh, P90X Plus...
I think I may be getting that. Great way to break in the new apt.
BTW, for anyone struggling through these workouts and not getting plyo or abs done:
Work harder

This isn't a miracle DVD, but it's well made and it gives you structure. If you abandon that structure or modify it to make it easier, it loses a lot of its impact, IMO. It's kind of like doing half of your daily work or chores and saying you'll do the rest tomorrow. Why not just do it today?
Seriously, this is only as good as you make it. I'm not a blob of fat, but when I started I wouldn't say I was in great shape. I still wouldn't say I am (%BF too high). Regardless, I had trouble with Ab Ripper, but I never stopped. If I needed to take a break, I swallowed my pride and did. If I wasn't doing a move right, I paused the DVD to take the time I needed to get it done correctly. I feel like as long as I'm working to do it right, I'm not wasting time.
Same thing for plyo. If you're having trouble, budget your time so you do half the disc, take a break midway, and then come back in 5-10 minutes. If you can't do that, just force yourself to get through a little more each time. Say you whittle that 20 minutes down to 15 next week. Then you get it down to 5. You'll eventually acclimate to it, as bad as that may be, and you'll be able to hammer it out even on bad days.
Maybe it's because I'm still a youngin', but I can't see buying into an exercise routine and quitting early on certain days. The results are so much better and so much more rewarding if you can find a way to trick your body into doing those last few minutes.
Also, on a related note, I firmly believe that none of the DVDs should be easy, either (outside of the Kenpo/Yoga/recovery week ones). If you're looking forward to a specific one because it's not as hard, chances are you need to modify it and make it harder. I can legitimately say that I do not look forward to feeling my muscles fail as I do curls, pushups, or pullups, but at the same time, I know that if they don't, I'm not doing it right.
I think Tony Horton said it best in another little YouTube clip I watched. It was about women walking to lose weight. Basically, he said to put yourself on an intensity scale from 1-10, 10 being that someone's chasing you down a dark alley with a knife and 1 being you're getting up from the couch. To burn fat, you need to be at at least 7-8. Obviously, you don't need these kind of analogies or a trainer to tell you this, but it helps to frame it in a very easily understandable way, and the same thing goes for weightlifting. You don't need to fail after the first rep, but you should be having trouble at a point before 12 reps.
I'm having the time of my life seeing the results and feeling the physical gains. I go to bed tired and dreading the next day's workout until I wakeup and don't feel the old, stupid aches and pains. I also don't feel as much extra fat baggage, so it's a win-win, IMO.