Some sets are short range (25-50yrds), some are long range (250-500yrds). Some I'm down on my miniumum power, some I'm at max power. I generally like my top end magnification somewhere in the 14-24x ballpark, which puts me 4-6x at minumum. If I'm hunting a set where I might be overlooking 300yrds all downhill, I might turn up to 20x while I wait since I'll likely see them coming in from a long ways off. If I'm watching 100yrds where they might get under me before I notice them, then I'll turn down to the 4-6x ballpark.
But, then again, I'm definitely one of the few people on here that prefers to use high magnification scopes. Sure, I CAN shoot out to 300-500yrds with nothing more than a 3-9x, but I definitely don't prefer to do so.