I've got around 800 rounds on the holosun 507c on mine with no issue. Theoretically, it should hold up much better on a desert eagle than it will on a traditional slide-mounted setup. The barrel of the desert eagle doesn't move, unlike the slide of a typical firearm. In normal use, it experiences the forces of suddenly being jerked one direction when the slide starts traveling rearward, then possibly an abrupt stop when the slide runs out of travel, then the force of the slide going back forward, and then another sudden stop when the slide is all the way forward. On a desert eagle, it just sits on the barrel and doesn't move.