I did a 12-week BB rotation at the end of 2015/beginning of 2016 because I had read about VFers who had amazing results with it. I did 5 workouts/week, each 30-60 minutes (average of 4:15 hours a week). I loved the workouts but did NOT get any positive aesthetic results. I lost all muscle definition and gained size in my hips/butt. I still don't understand why
For the last 4 months I have been focusing on Callanetics. In June I did Callanetics Countdown for 30 days straight and since then I do 3 Callanetics workouts weekly for a total of 3 hours. I pick a set of classes on the streaming site and repeat them every week for a month. I enjoy the workouts more each day... and they feel more and more difficult as my form improves. I love the functional results in terms of reduced stiffness, and improved mobility/flexibility. In terms of aesthetic results, I am amazed at how this method seems to pull everything in and smooth everything out. For me it is most noticeable in my waist/abs as well as my butt. Since plank moves seem to be the magical ticket for my upper body, I want to include some of the more recent Callanetics workouts in my rotation as they have more of these.
HTH!