Which Faction Is Easiest To Play In Horus Heresy?

Which Horus Heresy faction is the easiest to play?

It is a seemingly innocent question, but goes deeply into how the game plays and how players can learn the game. It is also the question that Gaming Gitz recently posed to me! A few conversations, and we have a new collaboration video out:

My answer here, for the sake of spoilers, is Iron Hands. 

But you are going to have to click on the video link to hear why (assuming that you can suffer my dulcet tones!). Enjoy!