Hi Katerchen,
If you are familiar with Cathe's other tapes, you won't have a problem with the choreography in the X-Train series. There's really a good variety of 'old favorites' and new stuff, so you feel right at home but you're also learning something new to keep it interesting. She also throws in some variations on old favorites which are very clever and make for a fun mix. The few times when the choreography isn't intensity junky style, it doesn't last very long so you DO NOT have to worry about your heart rate falling, especially with all the power 15s & power 7s around every corner!
I was fortunate enough to acquire all six tapes on the video exchange but I was just getting ready to break down and buy them. If I ever get a DVD player, I'll definitely be ordering the DVDs (no more cuing up)! I think it's really worth the money, especially if you like a variety of cardio. I actually only use the cardio sections that involve a step but I think it would be worth it just for that!
The strength sections are so effective and thorough, and they're challenging enough that it's something I have to grow with it. A refreshing change from all this 'light day' stuff flooding the market!
It's been so fun to mix & match sections, there's just a plethora of different routines you can design with the series! In fact, I think I'm going to post my favorite two day 'step junkie' routine later today just for fun!