I'm sure like many of you, back in the 80's I'd buy Tinks 69 and pour a little into the little 35mm black plastic film canisters with a piece of cotton inside and put them out all around me. Did that for 20 years and eventually realized I was just doing it all wrong and pissing money away. Tried Code Blue for many years. Eventually I stopped using scents all together.
My brother and I have had the most luck with Hunter's Specialty's Doe in Estrous scent wafers. Not sure what it is about them, but I will say they do seem to pull bucks in. He started using them before me and had all kinds of great stories...I was skeptical. I tried them out of curiosity and had similar experiences.
After deer season ends on Dec. 31st, I carry a little plastic Ziploc bag with me when I am scouting, logging, skiing, hiking, etc. If I find a nice concentrated spot of frozen doe urine in the snow I'll pop it out, let it thaw, and then bottle it and refreeze it for occasional use as a cover scent the following fall.