I know this is contrary to popular opinion,but mostly,my deer scopes are left at about 5X most of the time. Turned up or down as time and need allows. Most of the time, shots taken at 5-6X without moving. It seems for me,using a lower power setting is like looking at a smaller image of the target.I know,FOV and light gathering are better at low power. If your eye relief and focus are near perfect and you have good glass, You can get away with using a higher power.I have been doing this for years and cannot say it has hurt my success.