I'm hoping that this baby plays on average 2 - 2.5 hours, better if less. I know HH is going to be quite epic but anything that shoots more than 3 hours can be overkill to the point I shall just say 'let the Emperor and his favorite son screw each other till the Tyranid comes and pwnz 'em all'
I believe the 2-player system will help speed up things, better than with so many various players with varying speed of play and smack talking.
While we're on it, what would be the best average game time you think that is most ideal, for games something like this?