A lot depends on the bow I'm stringing. Generally I use a push/pull method. On recurves, bows with excess reflex and bows being built I'll use a stringer as to not stress the bow too much and in the first two examples, it is a safer method for you and the bow.
A setp through method is OK for self bows but can be detramental to glass or lam bows.
The safest all around method is with a stringer.