Your joints and back will thank you.
Those workouts are no joke. But, eventually you will want to work in more weights. I started on the unlimited, lost a bunch of weight and added muscle.
After about a year needed to hit the gym more to add more muscle, so now I go to OT about 2x a week and the gym 3x a week.
Cross fit will eventually lead you to the chiropractor or back to the couch due to injury if you are over 40 or not in great shape already. I'm not a fan of their jerky, uncontrolled movements.