LOVE LOVE LOVE my wii fit!
My husband was impressed with how out of balance he was, and since using it, has come back into line. It has helped me quite a bit, as I have vestibular issues. I am very dependant on my eyes or line of sight for balance, and this has helped me switch back over to allowing my body to do this more naturally.
I love the regular game for wii as well, but once you unlock the balance games you will have a blast, and be exercising without really stressing about it.
I vote yes. get one.