Last time I bought some was 3 years ago. Haven't bought since.
Usually lit up like 3 or four at the spot I was still hunting, maybe they are good in masking scent but I did not see any bucks come out. Only had a doe and fawn, and a single doe come out, that's it.
Maybe if you lit them everyday for like 3 days and had a trail cam, and then did the same thing with the trail cam the following 3 days minus the scent sticks you could see a comparison?