I disregard those that loudly proclaim that anything over 9X are for varmint or target only. (TOHeir)
Living, and hunting on east coast (MD,PA,WV,VA)most of my scopes are 4-12.
2 are Vortex 4-12X42 Crossfire II with BDC.
2 are Redfield Revenge 4-12X40 with Varmint Accuranger reticle. There are markings for 8",16",25". 8" for varmints, 16" for deer chest, 25" for standing coyote, or elk chest. Use zoom to bracket animal, gives you range to 600 yards. Go to 12 power, hold over on BDC and reap your rewards.
Wifes rifle is wearing a Vortex Crossfire II 6-18X44. It's on a Savage 110FP in 223.
My custom Mauser in 284 Win is wearing a Sightron S-TAC 4-20X50.
Most of my hunting is on a gas/power line with occassional fields. Shots range anywhere from 20ft to over 1,200 yards.
When i shot my doe last year at 413 yards, just as it was getting light, i was glad for the 12 power.