My biggest gripe with other chairs I've owned in the past is the cushion. This cushion comes as it's advertised (over 4 inches thick). It's a tad firm but it's very supportive and unlike other chairs I've owned, you don't feel the frame through it.
The massager is a vibrator with an off/on switch, and it comes with a fairly long USB cable to plug in. so i highly recommend this chair over all this is a game changer indeed