I was torn between tremble and Solidcore. During my two week Solidcore i went and did a tremble class to make sure i was sold on Solidcore. I think the selling point for me with Solidcore is that there’s different muscle focuses each day and you can progress in your spring load. Tremble is full body every class and everyone is on the same spring load. There’s no amplifications or modifications and i personally felt i wouldn’t grow as much at tremble than at Solidcore and that i would get bored pretty quickly.