Depends. I don't need shards but I always need energy, and the XP boost is great if I'm leveling guns. However, I refuse to do any DLC missions for the daily. They're just too damn annoying to solo at level 30, and they come up wayyyyy too often. But, if it's a pre-DLC mission other than The Black Garden (also way too long and annoying) I will probably do it just for the hell of it. Only takes about 15 mins anyway.