Ogryn - Mechanized Assault
Based on the leaks, Astra Militarum units popping out of transports will get +1 to wound. Running that through Unit Crunch accounting for rapid fire and their AP ability has a 6man unit of Ogryn at a 55% chance of wiping a ten man unit of space marines in one shooting phase, not accounting for their melee as well.
Definitely interested to see them on the table.