The board itself seems rather sturdy, the battery compartment door was easy to remove and snapped in firmly. The 'sync' button is inside the compartment, just like the Wiimotes. #1 son and I were set up in minutes, and we both stunk at the very first test trying to figure out what we were doing. It involved checking your balance, posture, and body control by having you hold off-balance positions for three seconds each.
Since the machine has your age and BMI before you do this test, we presumed that those things figure heavily in getting your initial "Fitness Age". I am a normal BMI, but only got through four of the five initial body control tests. The machine gave me a Wii Fit age of 42. (I'm not 40 yet.) By comparison, when my wife tried it later, her BMI was several points higher but she aced the body control tests with time to spare and was given an initial "Fitness Age" of 35.
We liked the wide variety of things to do on the game disk. The games aren't suffering from all being too much alike, and the Yoga, Strength Training, and Aerobic sections are easy to work into. Sure, there was one or two that I may not be ready for, but if I get better at the other ones, I'll be ready soon enough. The real question, will I be able to stick with it? Will I want to jog around my living room with a Wiimote in my pocket or do pushups on the balance board more often? Check back in two weeks.