Angie: I've previewed a few of the dvd's and have done the two cardios. This will probably be a bit random in the observations, but I don't have time to really organize what I'm writing, so please bear with me. I'm actually doing P90X, right now.
Supreme is not just like P90X. This is not a bad thing, BTW! But, for example, they are shorter workouts, there is no yoga, and even though the cardio is high impact for some moves, it doesn't have anything comparable to Plyo X. It also moves at a faster pace. There are pushups but no pullups (at least, I haven't seen them).
The music is non-descript rock, very P90X like, but it is played at a lower volume and I didn't even notice it on one of the cardios except when for a short time it was a bit louder.
I like the set on P90X more, but the Supreme isn't awful or anything. Tony Horton and his back up people are more engaged with each other, but again, not really a reason to not like Supreme. Tom Holland, who leads Supreme, doesn't do any of the workout, except to demo the move one time.
Some people like the instructor to work along with them instead of coach, it doesn't much matter to me, I'm fine either way if they are delivering a good workout. Although, I love how Cathe is in the trenches with us. Tom is not as "out there" as Tony, which could be a huge plus for some, but Tom does constantly talk through the workout. Neither instructor's style bothers me, I usually tune out the workout in terms of the chatter, anyway. Actually, Tom reminds me a lot more of Bob Harper's style on his Inside Out (or whatever they are called) but, Tom is lot less "no pain, no gain" and friendlier than Bob is (BTW, I like Bob, too, he's just different).
Again, the exercisers don't really interact with Tom, much. They are all super fit and look pretty young. There is one girl, Sally, I think, who is really ripped! There is one girl who is very fit and a bit "enhanced," I love her hair. All the ladies are very fit and pretty. I thought Sally's form was a little off on a couple of things (rounded back) but, Tom didn't seem to mind, so it may have been just me. The guys are cute and fit. One has tattoos. Not as much variety on the exercisers, like Cathe has.
It looks like they reused the footage of warm ups and cool downs. The biggest stand out differences are no pull ups (that I have spotted so far) which, I think, the pullups and pushups are what really make P90X, there is also no plyo, and no yoga. They are much shorter workouts (again, this could be a huge plus). The leg dvd clocked in at under 30 minutes and when you think about how you work your legs in both the plyo and yoga, that isn't a lot of leg working out, over all. I like the Supreme cardios better than the KenpoX and CardioX. One is Tabata style where you work hard 20 seconds and rest 10 seconds. The other is on 30 seconds, off 30 seconds. Both are tough, about 30 minutes and non-complicated but effective moves. I'm not sure I like the weights moves in the cardio, because some of them are not full body and my heartrate went down. I think I would add lunges or squats in where I could to keep the hr up.
The nutrition book is mostly menus, not much in the way of guidelines. I think there is more info in Tosca's books than in this pamphlet. BTW, I would have loved to see her in the videos and was kind of dissapointed she wasn't in them but only because she is very aspirational, especially if you know her story. I thought it was funny how much she talked about BM's in the beginning of the booklet. And she wants you to drink 4 cups of water first thing in the morning. The menus are a little different for men. It doesn't go the full 90 days, but you would just repeat the earlier stuff, anyway.
Overall, for the money it is a great set. I don't think it is a duplicate of P90X, which is misleading. It is a great set on its own merits. But, I've used P90X at least 3 times and feel I've more than gotten my money's worth since I've used it a lot and the emphasis on pushups and pullups have always gotten my body to respond in a great way. Same thing with STS.
Oh, yeah, the set is not chaptered like P90X and no premixes like Cathe offers. I like workouts that are well chaptered and that I can fast forward through the "check with a doctor or you may die and we won't be responsible if you do" stuff. Its not as bad as some of Jillian Michaels where you have to go through the same talking interview each time to get to the workout, though.
I hope this helps.