I've tried several different scopes over the years from 1-4x up to 4-16x and for the predator hunting I do, I prefer a boring old Leupold 3-9x40 with a duplex reticle. In fact, I prefer that scope on all my hunting rifles, whether it be a deer rifle, elk rifle, or predator rifle. 3 power is low enough to find your target and give enough field of view for close targets and 9 power is enough magnification for when you have to reach out a bit. As far as light gathering, the 40 mm objective gives you plenty of exit pupil throughout the range of magnification to have plenty of brightness. If you think you'd might need more, step up to a 50 mm objective. These are my opinions only and what works for me. Good luck.