The Genital Grip is awesome, There I said it. Here is why. It pumps up your blood pressure and over time cam increase your penis size. It can change your penis’s upward angle. (I personally gain an extra 20 degrees of upward angle) It is adjustable for an entire endurance session. That means high blood pressure in your penis, then loosen for normal blood pressure, then re-tighten to enlarge, then loosen and it all takes about 3 seconds each time. Different blood pressures feel different orgasmically and the change in sensations helps keep things interesting.
The Genital Grip does not control the orgasm and it is not required to learn the Longasmmm method but I use it every time except on videos when I am proving that the Longasmmm equipment is not required. Other than that I use it every time because it is interesting and it feels better. And the boost from constricting blood flow results in a noticeable increase in penis size.