I had to do it, I had to try level 3 today. It is VERY hardcore compared to levels 1-2. There were some moves of which I will never be capable. I don't mean to sound negative but I have a severely inflexible upper-back so I cannot do the table move correctly--my upper-back won't allow it. Also, some side-plank moves are impossible for me because a single elbow joint cannot handle supporting my body weight. Jillian usually incorporates a modified version that makes it still possible but this workout did not have one. When I encounter situations like this, I do something similar that is physically possible for me. I don't take a break! That is one perk from when I used her website last summer, every move had a link to a different move that worked the same muscles in case someone couldn't/didn't want to do something on that day's workout plan.
I will say this much, I really enjoyed this level despite it's difficulty. I plan to go back and finish level 2 but I am excited to do level 3 again soon. It's fun and it introduced me to more cardio moves that I can do without hurting my ankles/knees.