Bulk, for several reasons. Price of course, just compare the cost of 2 oz of bulk with a tin of the same blend. And most or many tins don't even have 2 oz. Then, best practice is to transfer it to a jar anyway, and usually I already have the needed jars. Also, you can buy the bulk in one-oz quantities if you are sampling to see if you want a greater quality. I have never experienced a difference between tin and bulk in the same blend. On the con side, I do like tin art, and I like the sense that a tin is premium tobacco, but both of these are aesthetic and not factual. Tins are easier to store, take up less space, if you may hold or age the blend for a while. But for most purposes, bulk is a better deal on the same tobacco, so usually, if it is available, bulk makes more sense.