I've only had the Bigmos for testing for *ONE* full day, so I could only walk around my neighborhood and snap some "quick and dirty" shots. All these images are handheld at full throttle --> 500mm (800mm FOV) and F6.3 (wide open). Most are resized with basic levels adjustment and USM of 150, .3, 0. IMO the images are impressively sharp, clean, with nice contrast and colors. For $950 USD, the new Bigmos is quite a bargain. Getting 500mm native (800mm FOV on APS-C), with 4-Stop optical stabilization, ring AF with FTM, and this kind of build quality (with large tripod collar, hood, and carry bag too) at this price is unprecedented. The AF speed isn't the fastest around, and the OS is a little erratic, but overall, all things considered, this lens is an exceptional value.