I have had exactly the same experience with scent wafers as I have had with every other variety of estrus scent--in a word, sporadic.
I have had mature bucks come in and put their noses an inch or two from the wafer in great curiosity, and I have had them walk right over scent trails laid down only 20 minutes before and not even stop to investigate the trail for a moment.
Nothing commercially marketed--no liquid, gel, or wafer, etc.-- can hope to compete with the real scent of a doe in estrus. On the other hand I have laid down a scent trail using wafers, had no luck with it that day, hunted the same spot the following day, and had bucks with their noses to the ground following every inch of that trail.
One thing I have learned is that does of any age will usually re-act negatively to the scent of a doe in estrus. They won't spook madly, they may even hang around long enough for a shot, but they will usually turn around and go back the way they came in a state of nervousness or unease.
So if you are a meat hunter, you might want to avoid using estrus scents around the time of the rut.
I have had lousy luck with attractant scents at the same approximate elevation as myself when I am in a tree stand. They have brought deer in and have led the deer to look right up at me in the tree and wonder what the Hell I am and leave quickly. For firearm hunting that might not be such a disadvantage, but for bow hunting. I have found it to be too risky--but to each his own.