I was able to use this for the first time this weekend at a party, and the woman REALLY enjoyed it. I have not used the more expensive Hitachi before as a comparison, but this seemed to do the trick quite well and we had no complaints. It can't be used while charging, but the battery seemed fine during our use. I don't know how long it would last for extended sessions or multiple sessions, but as far as power and vibration, it certainly has enough to pleasure a woman as much as she needs. Recommended, especially for the price point.