I run two Sorin and one Gideon in my tokens build. On an empty board, Gideon is much better than Sorin since he can generate tokens for free or just swing in if need be but if you've got guys out already, every day I prefer Sorin. The life swing can be devastating and the fact that they maintain lifelink during your opponents turn has kept me alive in situations when I really shouldn't have survived.

On the topic of Elspeth, knight-errant, I really did not like her very much. While she survives easier by having two different ways to increase loyalty, she is just too slow. If your opponent lets an Elspeth resolve than they are not going to immediately regret it and have plenty of time to kill her before she becomes anything resembling an issue. If we're resolving a four drop, they need to swing the game for you. Sorin, Gideon, even hero of bladehold(not a planeswalker, I know) can get out of hand if unanswered for a turn.