Hi Melanie,
I just did the first disc for Meso 3 today (fyi, this is my first round of STS) and I survived!!! Anyway, I agree with the others that you should give it a try. Because of the rest period between exercises and alternating muscle group focus (chest, rest, back, rest, chest, rest, back, etc...), even with the heavier weight, you will find it more manageable. Good Luck!