Whenever black book IX comes out I'm planning to order 3x Castellax with Praevian to join my AL army. But I can't decide if I go for the power blade + multimelta option, or the darkfire cannons. The mauler bolt cannons feel less attractive since banestrike ammo don't seem to be much of a perk for AL.
I see that power blades can be a good alternative to Contemptors in ZM. Also the would bring some good close combat capacity to a quite shooty AL army. But the darkfire cannons feel fluffier and with Alpharius would be quite devastating.
What do you you think? 3x Castellax is a quite an investment so I'd like to choose a type that I'd get most play and satisfaction out of.