Ballet Body Volume 3 - Lower Body by Leah Sarago is a tough workout! Perhaps I'm revealing myself as out-of-shape and over-the-hill to say this, but I'll admit that the first time I tried this DVD, I cried uncle 20 minutes in: I gave up and spent the remainder of my workout time lying in a heap on the floor! I don't think I've ever done an exercise DVD that's so intense on the legs, especially the thighs. The good news, though, is that after you've done it a few times, it becomes substantially more manageable. So don't give up!
The workout is 55 minutes in length. The first 40 minutes consist of challenging standing moves and some floor work. If your legs can survive that, the final 15 minutes are spent in a nice stretching series.
My only micro-complaint is that some of the music is a little annoying (like the part that sounds like "Careless Whisper" as sung by The Chipmunks). But other than that, a great lower body workout!
Other reviews here, and you can head to Leah Sarago's site for more information. There's also a clip of the DVD available on YouTube.