My personal feelings is that there is nothing better than natural scent. In the past, I have live trapped coon from where people didn't want them, then use the cage and coon as a drag and run it up a tree, with the pup you are training out of sight. You can set it up like this for short tracks for a pup just starting out, then when they get firing on it, turn the coon out in a place you know well, then wait a while and turn the pup out. As long as the pup can't see the coon and is using its nose it will only help. You can change up the amount of time you wait before turning your pup on the track. I have also used water so the scent is really out there. I don't think you can substitute the real deal for something in a bottle, but that's my opinion. I would recommend using two different vehicles for this so your hunting rig doesn't smell like a coon.
well said michael! Ive done it exactly like that and it worked great. never messed with bottled coon scent, just took live coons trapped in the city and turned em loose in a field. if you turn coon loose in the timber it just climbs the closest tree and there isnt much trail to run. I turn them loose at least 100yds from the woods, then go get the young dogs and lead them close to where i turned loose.