Going to be the odd one out and say Stalker Bolter. I've always preferred to dispatch my foes before I have to see their ugly faces.
I want lightning claws with ocassional sorcery. Shred up close and when i feel too lazy to launch 10 ft away just annihilate them with a doomblast. Hope my battle brothers can provide covering fire though so i dont have to worry about and devestators or rhinos that id be defenseless against.