The most obvious, and only, flaw of this vibrator is that the motor is not very strong. Of course, the wand is quite slender so it's not like the manufacturer had much of a choice with which size motor to install. I have used this vibrator a total of six times so far and was only able to orgasm one of those times, the first time! Unfortunately my repeat attempts for satisfaction were going unfulfilled due to the Zini hua's lack of strong vibrations. You would think that this would not be a problem for this toy because of the menu of settings it has available. There are three buttons, a plus sign, a minus sign, and a circle. To turn it on, you press the plus sign once and it releases a continuous vibration on a low setting. To increase the vibrations, keep pressing plus. If you want to go back down a setting, press the minus button. The circle button allows you to initiate the toy's pulse setting. Pressing it once while the vibrator has already been activated will cause it to repeatedly pulse slowly at 2 second intervals. However, if you hold down the circle button, the pulse setting will be randomized, which is a lot less boring! While the pulse setting is activated, you can still use the plus and minus buttons to adjust the vibration strength. Also, vibration sound coming from the toy is not very loud, but when using the pulse setting, it becomes noticeably louder.