i have the Horus Vision version and i didn't particularly care for at first because it bulges out the side rather far because it's a bulkier item than the ACI most use. found a cheap weaver mount in my junk box that moved it closer to the scope and some protective pads that i have around my scope to protect the turrets, ACL, and my crosshair locking device that all stick out from the scope making them vulnerable when the gun goes in and out of the scabbard. of course i've used it a little and rather like it now. the main reason i like the Horus is because it also gives the angle as well as the cosine equivalent. reason being is i hunt by myself and when it's time to find something on the other mountain, i take not only a compass reading but an angle reading to help find the spot. this really helps zero you in on where the animal is. it also has the level on it, which is one less piece hanging off the scope. it's not as sensitive as the other bubble i've used in the past but i think it works just as well.