I don't have MIS yet. But I ditto everything you said about Cathe and how important personality is. I'm one of those people who loves weight workouts, but DREADED any cardio, in any form. I did one step routine occasionally (buns of steel step 2000), and only did it because I liked the personality of tammilee, donna and tracy, and I loved the squat workout routine at the end. :+
Then, I got my first Cathe Step tape and I actually LOVE doing the step routines now!

I can't believe it. Actually, no one who knows me, can believe it. I get up in the morning, really pumped to workout with Cathe. She ROCKS! I love her peppy attitude. And I think the coolest thing is that for some odd reason, she feels "familiar" to me. I think it has to do with having seen how YOUNG she was in her Step In Motion tape (what a doll face), and then seeing how she has matured into such a beautiful woman, and developed her incredible physique, in each of the other tapes I now have. And her "crew" is great too: lots of different ages, body types, and REAL smiles (the drone smile, can really grate on my nerves on some of the other instructor tapes I've seen. lol).
I just received CTX Upper Body Split, and watched it last night. I've never done endurance wt work, so I was exhausted just watching. I can't wait to try it today, though! I can see why she is so easy to get addicted to! I wish I had known about Cathe and this forum, many years ago.