They work great for skeeters but don't help much with gnats. I always wear mesh netting over my head when I hunt the deep woods even with a thermacell.
Seen 2 turkeys ten minutes after I got on the stand (4:45) and does started coming in right after that. Not sure how many total I seen but I know there were at least 6 different deer came by. I must have had a half dozen squirrels above me because they were constantly dropping acorns on my head...