Funny, before I discovered Cathe, Firm tapes were the end all-- I used to take a 45 min walk on a low energy day..
Then AFTER discovering Cathe, I use my Firms as an alternate when I am not feeling like I can take on the world! Cathe has bumped up my fitness to the next level for sure!
Of course there are times when doing TT and /or Supersculpt, that I am challenged, and they also are great for my THR, but Cathe has overall done a great deal more for my endurance.