both are unrivalled in their field and both seem to attract enmity from the most powerful of people.
though it is not stated anywhere, i find it hard to believe that luc besson didnt take a great deal (at least visually) from "Golgo 13":
moreover, their origins are both shrouded in mystery. we know Léon is an immigrant, but thats about it. we know practically nothing about where Duke Togo is from (i havent read the manga series, so if anyone has any more details on this, do enlighten us please).
they do differ from each other in one key aspect of their personality, though.
empathy.
Léon exhibits an almost child-like sweetness about him, while Golgo 13 virtually shows no emotion whatsoever. i doubt Duke would take on a ward of any kind, no matter the circumstances. he works alone, strictly alone.
Léon shows Mathilda the basics of taking a mark out at a distance:
Duke Togo displays his awesome sniping abilities:
while Léon is the man-child, virginal type, Duke Togo is the hardened (no pun intended), stone-cold womanising type (paying for your new spoofed-up car and modified m16 by bedding the sexy girl who made them for you is straight pimp!).
i guess its up to you to decide what kind of assassin you prefer...
IMDB:
Golgo 13 (1983)
Léon (1994)
more clips (*SPOILERS*):
Duke Togo vs. The Snake
Duke Togo vs. Gold & Silver
Léon and Mathilda knock on some doors
Léon vs. NYPD