One of the simplest but truly useful accessories I have bought for a mobile setup. I mainly use it in combination with the Ulanzi MT-08 and iPhone 17 Pro Max for night photography, motion blur, long exposure/light trails, and time lapse shots, and so far I have had no issues with stability or the weight of the phone. Although the iPhone is quite heavy, the clamp holds it very securely and generally gives a lot of confidence when shooting outdoors or during longer shoots.
What I liked most is that it doesn't look “cheap” or flimsy like many smartphone clamps in this category. The rubber pads hold the phone properly without slipping and overall the build quality feels much more like a premium accessory. It is also very convenient that you can easily mount it both vertically and horizontally depending on your setup or the type of content you are shooting.
Another big plus is that it has two mounting points, which is very helpful if you want to set up a more complete mobile setup. Personally, it has been very convenient for me because you can easily add a small LED light, microphone, cold shoe adapter, or generally extra accessories for video/content on a rig/tripod without messing with weird hacks.
The only issue I personally had is that with bulkier/thicker cases it doesn't always fit as well and you need to pay a little more attention to how the phone sits. Also, although it holds the phone very securely and you generally don't worry about it falling off, the clamp feels a bit more “stiff”/plastic than I expected.

For a mobile photography/video setup, I think it’s one of those small accessories that you end up using all the time without realizing it, especially if you shoot a lot of content with a smartphone instead of a camera.