Well, I think they do to an extent. I do not believe though that any scent killer product can truly get rid of all human scent. A little cover scent, and using the wind to your advantage, and I think you are fine. Heck, I have even used diluted apple cider on occasion when hunting in an apple orchard, or if I forgot that, I would take an apple andcut it open, then rub it on my hat, shoulders, pants, etc. Seemed to work for me. Heck, no deer that is downwind of you in 20 mph winds is gonna stick around too long, scent killer or not.
I always shower with scent killer body wash, use scent killer and a cover scent and then hunt downwind of the deer. Does the scent killer work? Dunno for sure, but the entire program seems to do the job.
Rather than spend my hard earned pennies on those cool Shoot-N-See targets or even the preprinted targets at sporting goods stores, I save a few bucks for weekend plinking sessions by using paper plates as targets. A 100 count pack of paper plates costs less than a 10 count pack of preprinted targets.
If you are playing with something like a semi auto AK, or building a young shooters confidence with a 22 or shotgun, those big eight inch blanks are perfect for putting holes in all...