A lot of great input here. I think Daryl's simple point "a lot depends on where you hunt" is important. To that I would add a lot depends on how you hunt, and when.

A lot of this discussion necessarily centers around marksmanship rather than hunting. However, the older I get (and maybe the worse my vision gets LOL) the more up close and personal I like encounters with game to be. I realize this is very difficult when working on open plains. I generally hunt in deep woods so it's feasible (and more necessary). Successfully positioning myself close to animals in their natural environment is the challenge and goal. I have always respected bow hunters for their ability to do this, although I don't feel arrows are always the most humane killers. To me shooting an animal at 300 yards that has little chance of being aware of my presence just isn't the experience I want to have (although I fully respect that for others it may be). I think a lot of the dangerous game hunters on this board similarly pass on the chance to target from long range to get the challenge and thrill of stalking in as close as possible.

I hunt only with iron sights (usually a peep) on leverguns, single shots and muzzleloaders. Most of my shots are inside of 75 yards (a lot inside of 50). A shot over 100 yards in the timber I am unlikely to get, and over 150 across a field I would be hesitant to take offhand. Light conditions are another factor. Deer in particular are likely to be spotted around dawn or dusk, which can make a longer shot more iffy even in the open or if you are in a stand or blind in the trees where you really know your shooting lanes. I have actually considered going to a scope for just this reason, in the context of achieving a one shot humane kill. Weather (rain, snow, wind) is also a factor, even when in open country. And, of course even in wilderness I like to be aware of what is behind and beyond my target. When in doubt I pass on the shot.

I guess the bottom line for me is I seldom need or want to worry about longer ranges, but the terrain, the conditions, and your goals are all important factors, along with your marksmanship.