I have used a bunch of Spypoint Cell cameras including the Cell Link that you connect to a trail camera that you already have. Some have worked well, some have failed, customer service can be spotty. When they work, they work well.
The best in my opinion are the solar Link Micro S LTE cameras - with the solar panels and lithium batteries I have one that I use for property security that has lasted over 2 years without touching it. You can still find them, and although initial set up can be a PITA, they have worked the best for me.
I have one solar and 2 non solar Flex cameras and they dont impress me (other than memory card set up being done on the camera and not on a computer). There are complaints of water leakage into the camera itself, although I havent experienced it.
They come with straps, but I use my own adjustable mounts instead of and mount the camera 12 - 14 feet up in trees, pointed downward.
However the 1/4x20 threaded receiver in the Flex series are in the wrong place. Being located on the top back of the camera body limits how much you can angle the camera downward before it bottoms out on the tree. The receiver should be on the bottom of the camera, not on the back of it. A black bear climbed up the tree and pulled one camera out of the screw in hanger. It pulled the threaded insert right out of the camera body and left it on the hanger.
Just my experience and thoughts.