I usually give my commendation to the DPS for DPS love since I am a DPS person lol. And if the Tank or Healer really stood out than I will give it to that player. But since I play on PS3 and its really hard to quickly get out of those cut scenes I end up giving it to the person that waited. I always give commendations in dungeons but not Guildheist all the time, the thing makes you feel rushed to collect your xp and stuff lol