Table comparison with Map Op transform vs Table comparison with hist preserve

What is the right approach:

my source has last_Updated Date field.

Scenario 1.) source > tbl comparison > Map oper > target

V/S

scenario 2.) Source > tbl comparison > history preservation > target

Both are doing the same thing, what is the benefit of using one over other.

I use source based cdc approach, which is much faster, but sometimes i see the above methods used.

Thank you all for the helpful info.