Wendy, I am doing an STS/Tonique rotation right now and really loving it!! I've just finished the second week of meso 1. So far I've just done tonique for the leg work, but I may sub in some BBL here and there, too. I'm also counting Tonique as cardio, and I'm condensing the rotation where I rotate the three on a two day on, one day yoga type thing, for instance:
day 1: chest/shoulders/biceps
day 2: back/tri
day 3: yoga
day 4: tonique
day 5: chest/shoulders/biceps
day 6: yoga
day 7: back/tri
day 8: tonique
day 9: yoga
etc. I'm absolutely loving it and having great results! I know it may be a bit unorthodox to some, but it's really working for me and every day I'm so psyched for whatever I'm doing. I'm adding in walks where I can, and I may try to work in some cardio dvds here and there, or a run.
Oh, and I also tend to get huge quads, and my legs are really benefiting from laying off the weighted leg work and focusing more on the glutes/hamstrings.