I just finished doing the weight portion (upper body premix)on the 4DS. It was totally different than GS. It wasn't easier than GS but I do think it was harder in some cases. I think the shoulder section was harder than the shoulder section in GS. I'm not sure I liked the tricep section but triceps are my least favorite body part to work. I loved the chest, back and biceps portions. It does have a different feel than any of her other weight workouts. It's long(67 minutes) so I'm not sure how I'm going to feel tomorrow. I tried to go as heavy as possible. There were a lot of different moves so it will add a variety to your workouts. There were rounds for Chest and Back and Tricep and Biceps. So you would work chest and back, then work chest and back again. So you weren't doing all chest work then all back work. The same was true for the Bicep and Tricep section. Overall I really liked it and can't wait to do it again.