Watching the wind is the most criticle......
I use my own cover scent formula...Baking Soda mixed Hydrogen Peroxide
vinella and water.
I wash my cloths in this,shower in this and spray on my clothing befor walking...
I also use scent glands off of mature deer as well.......
But I also hunt with smokers (used to be one and still am one after a "KILL") and they harvest as many mature animals as I do or anyone else for that matter...
Cover scent are not long lasting,(maybe 10-15min)the minute you work up a sweat on your bobyits absorbs into your clothing and animals smell it almost immediatly...
I do it cause the first 15min of my hunt is the most critical time for me
thats the only advantage I can see using them,
I always pay attention to wind thats whatgives me the success...