For a long time I dismissed the charcoal hype as just that, marketing hype. Why, well it made me feel better about being unwilling to spend the money on one.
If you research the technology behind the method you will be convinced its sound logic. To be totally effective you would have to make it air tight.
There are a half dozen or more makers now and as a result the price has dropped. I picked up a ScentLoc lined shirt and later a head cover. No pants yet, but I've only got $62.00 invested. I figure, Advantage Timber hunting shirt = 30.00 Head cover = 12.00 so the ScentLoc cost me $20.00 I've wasted more on worst things.
I took it bear hunting in late August and found the head cover far to hot to use and even the heavy shirt was to hot.
Some guys stink, some don't. I'm sure that has an effect on the results. As for conclusive evidence that it will do just what the manufacture claims, you will never have it. Grunt on a call and 10 minutes later a big buck comes past. Was it the call? Did he even hear it?
I rarely get busted buy deer (that I know of) so how can you be sure the suit is the reason for not getting winded? It would take a pile of deer over a long period of time to convince a true skeptic. Yet, look at all the hunters that swear by them. Not just the magazine writers (who get them free, and are bias of the most part) nornal guys with no more money than you or I.
On the other hand if you are not on a quest to kill the biggest baddest buck in your area you don't need it. It's better to be lucky than good! I've been lucky! Maybe the ScenLoc will help me become GOOD! The woods will not be safe.