I don't buy both of the same blend either. It is always one or the other for me.
In theory, they are all the same. Bulk is made in large batches then shipped out for by the ounce sales, and tinned is made in large batches then divided up for small tins. The blend is the same, or is supposed to be.

FOR a definite answer, it sounds like a job for @JimInks . Not many have smoked more pipes than he.