This toy has been a game changer for me. The rings are comfortable and tight enough to provide a hard erection. Battery lasts reasonably long for two or three sessions. The app is average and sometimes the Bluetooth range is too short that you have to pass your phone by your butt to send a signal. The vibrations are amazing and it makes you euphoric. For a beginner like me, it will take time, a couple of uses and practice to get it all in comfortably. Using both the wiggling and the vibration felt amazing, but it can be overwhelming for beginners. Anyway, I freaking love this toy, but there's a problem.During one session I was tighting my "bottom" muscles around the device to increase pressure (I wasn't choking it, just tighting moderately). Suddenly the wiggling stopped and it never worked again, only vibrations. Tried to get a refund, but claim window was over. It's so unfortunate because I like this toy and was probably one of the best purchases I made last year. Anyway, be warned, excessive pressure will in fact damage the device (as stated in the manual). Still, even without the wiggling, the vibrations are amazing and I enjoy using it. Have fun with the toy if you buy it!