Well at the risk of being accused of threadomancy I currently use a Deathwing army with GKs taken as allies. I find the Brother–Captain's Ld10 psychic hood invaluable in many situations, and his squad's S6 Nemesis is just an awesome tool to have available in the Dark Angels
extended toolbox.
Fluff goggles are definately left back on the Strikecruiser when I play....
Cheers
I