For those that don't want to mess with making your own flags, MTM Case-Gard offers a very inexpensive flag and pole setup that's worth looking at. The poles are only 33" tall so depending on the range, you might need to make an extension. I saw one of these yesterday...they're everything that anyone short of a serious competitive shooter would need.
Here's a slow motion video that shows just what's going on in what would appear to be light (< 10-12 mph) conditions. Watching it a few times will show much more than I could describe....mainly how the air moves and progresses across the range. Pay particular attention to the flag nearest the bench as this is indicative of what we'd feel at the bench. I'll guarantee you that if you pressed the trigger in several of those situations even when the wind 'feels' the same at the bench, that bullet is going to park itself North of 1/2" @ 100 yds. from other shots.
