The worst, in my opinion, is on the TriSets workout. It's a screeching electric guitar without any back beat or rhythm. I know that I could put on my own music, which I will in the future. But why do I have to fool around with that? Working out at home is mostly an issue of convenience and if I have to mess around with finding my own music, the convenience factor goes down. Also, I feel like because there isn't a beat, the moves are done TOO fast. I've done other workouts, such as P90X, that do not use music with a beat and I'm totally fine with that, but with P90X you're able to go at your own pace and have a set time to get the reps done. Not with TriSets. You have X amount of time to do 15 reps and if you have to slow down, you only get in 10 or so. And on top of that, you have to listen to that terrible screeching guitar.