I got my BodyBugg and have been wearing it for 4 days. I have generally sensitive skin but the band doesn't bother me at all - it doesn't have to be on tight at all, and I forget it's there after about 5 minutes. I keep it on pretty much 24 hours a day except when showering.
First the positives on having more information - even after these few days, it is painfully clear that I have a very sedentary lifestyle as I watch the graphs online. I have an office job in a small building in the frozen tundra of Minnesota, so I have absolutely nowhere to walk during the day. On these days, I burn about 2000 calories (I'm a woman, 5'4, 193 pounds, and 27 years old). This definitely gets me motivated to find more ways to be active.
On New Year's Day, I didn't have to work and spent the day with the family. We went to the zoo, out grocery shopping and for a walk at the Mall of America - nothing too strenuous, just more active than sitting at a desk all day. On that day, I burned 2500 calories - obviously a huge difference!
I have not yet made it to the gym with my BodyBugg but I hope to this weekend to compare my heart rate monitor calorie burn to the BodyBugg. Having used a HRM for a long time, I can say that my calorie burn charts look "reasonable."
The online software is very interesting - you enter your food, it uploads your activity, and shows a deficit. Since the commonly accepted formula is 3500 calories in a pound, if you burn 500 calories over what you eat each day, you would lose a pound a week.
Unfortunately, the food part of the program is terrible - there is next to nothing in the database so you end up manually adding almost everything. Since I'm not made out of spare time, I end up faking it... picking something similar and forcing the portion size to approximate the calories I want. I actually follow Weight Watchers so I largely ignore the food part and eat my points. My Weight Watchers points are 25 daily, which seems to translate to 1200 calories. This makes me a little nervous because I believe that is about as low as you should ever go on calories, and I think WW will let people go down to 18 points or so.
They also push their brand of supplements a little too hard on the website.
I will report back on the accuracy of my "predicted" weight loss via the BodyBugg versus what actually happened after a couple weeks, after the water weight is gone.