Every day, usually Telesto. But on days when I need it for a special purpose (solar or arc kills), I pull out the Ashraven's Flight or Plan C or The Vortex or Susanoo. And for Crucible when I played, Telestos explosive rounds worked really well for people covering and shooting in doorways. Got a couple of triple kills when guys would look out, I'd stick 'em with projectiles, they jump back to their buddies and the detonation killed all 3. And "Plan C" in Crucible for those panic reloads on primary for an insta fire shot too.