I bought the n-charge system and tried it with my Sony notebook computer. The product said that you would be able to watch 3 dvd's, etc. with the time allotted. I ran the system quite a few times to give it a chance to break in. It never provided more than 4 hours and five minutes of continuous use...1.5 - 2 movies. More than the battery that came with my computer, but not even close to 10 hours worth. I'm glad that Brookstone has such a good return policy.