It is used alone, with EM, or to add depth to other
tobacco flavors.
It is quite strong, thick, and dark, so diluting it makes it much easier to deal with.
Best way to figure out how it will work is to make a sample batch with your TA dilution as the only flavor.
What it taste like depends on the extraction method and the tobacco used to make it. Some are ash-y to me and some have more of an aged tobacco flavor. (Like cutting a plug out of the old leaf in the barn before hanging the green leaf if you've ever worked tobacco that would make more
sense. I sometimes forget I've had an unusual life.)