Boardbumps and Kami... and all others keeping the stoke ablaze through all the years...
Technically, anybody when he/she manages to keep flow and power to their turns, using the turns and good positioning to accelerate. A lot of the vids posted by forum members are great for this, Goatman, Dogman, Casso, ... and a whole lot of others, whatever their abilities.
I must say that the first rider who have really impressed me was Kevin Coffman (blue board) in this video:
This video was a kind of a revelation for me.
Contest riders, I don't know. Often they had an impressive style in freesurfing but then progressively their style get "polluted" by the contest judging criteria into just a mechanical speed gathering aimed at just one big acrobatic maneuver, tail slashing and loosing all their speed. The Vaz brothers latest video "the find" is impressive, though.
PS: thanks HumanCartoon!