With regards to “easy to direct away from the no-go places”, I am envisioning the usage of ultrasound at the bottom of the shaft, which is right next to the balls. Where exactly on the shaft should the device stop? Or even besides the balls, aren’t there other important organs near there? I’ve seen people say they put their penis on their leg to use the device, but even doing that it seems like by the time you get closer to the base, you’d still might be hitting something important inside your body in that lower abdominal region.
If it is safe, the science does seem good, but it’s strange there’s no picture proof from anyone doing this (that I can find). If this is really the best way to do PE, some kind of visual proof should exist by now and way more people should be doing it. The device is not too expensive, but still not something I want to just waste money on.