I have the original and a FF3. The 3 is better because you can change the battery without taking the top off, but mostly because you can leave the brightness on AUTO or set it manually. Some light conditions can fool AUTO modes, leaving you with the wrong setting. I'll never buy any again without a manual setting.
They're light and compact and reliable. Not sure how much impact they can take. The open design lets you see more around the sides. The cover on the FF3 lets you shoot with it in place. A FF4 is coming soon.
Next up for me to try is a plain old Leupold FXII 2.5. With rings it should only be a couple of ounces heavier than the Sparc 2, the view is better, and no batteries. I have rings on order and in the meantime I'll keep playing with red dots.
