Hi Christina
I started a SS rotation a few weeks ago and I really like it! I didn't think that I would because I rarely like any instructor different from Cathe! But I also think that mixing things up is very good for your body.
FYI: I have been adding in 3-4 hours of cardio - both imaxes, KPC, and if possible, Bootcamp or another kickboxing tape such as Powerstrike. I haven't been able to strictly follow the suggested SS rotation since I make sure to do my cardio in the morning and then I don't always have the time to do the SS in evening. I like all the SS workouts except "Shape it Up," which is too long and boring (to me). I was very pleasantly surprised with "Cool it Off," which is a one hour stretch workout. I have never done yoga but loved this workout - you feel soo good afterwards!
Also, I have had excellent customer service from Beachbody. In fact I am planning to buy the P90X series soon.
By the way, the Slim in 6 series is much easier than SS. If you have been doing Cathe workouts for awhile then I would suggest SS over Slim in 6. My mother is doing Slim in 6 now after many years of running 5 miles per day and she is seeing results.
Hope that this information helps you to make your decision.
Best Wishes,
Angie