Board Thread:Warhammer 40k General Discussion/@comment-66.206.224.153-20131222032846/@comment-74.108.217.222-20140829191438

I would say the Spacewolves for assault missions. The Salamanders for escorting and protecting Imperial citizens since they are one of the most humane chapters. The Iron Snakes usually send just one brother to fix a problem. That's totally badass and combat efficient. The Flesh Tearers against Orks. The Black Dragons against zombies/cultists. Greyknights are awesome against demons. Deathwatch against Xenos. The Ultramarines are Codex followers but you do have exemptions like Uriel Ventris and his loyal buddy Pasius.

Within the Imperial Guard I would say Gaunt Ghosts and the Redemption Corps for infiltration.