At the start of this review I was skeptical that this sheet metal would actually make a difference. As a result of the tests, I realized that this device is 100% worth the investment. The range extender is very easy to install and offers instant improvements. I climbed from 1301 feet to a whopping 2667 feet (doubling the distance!). I have attached my DJI GO flight card to verify my details. Note that I haven't been able to get that distance on every flight I've made, but in any case the range has definitely increased on every flight with the extension. Pros: Significantly increases range by reflecting the signal 360 degrees in one direction. Simplicity. for installation (be sure to remove the plastic!) - Slightly increases the weight of the controller. Cons: - Can easily slip off the antennas when the controller is upside down. - Makes installing the phone a bit more difficult. be the difference how far you can fly (like you'd expect)