I'm half way through my exotic bounty now for a shotgun I think.
I've actually had really good luck overall. I've got legendary's in every a lot bar Heavy weapons and an exotic to come.
Admittedly 3 are from the crucible but I do have an off glass purple in the vault.
However I don't love my Legendary pulse rifle. I'd rather any of the other weapons.
And for crucible I use a level 17 green assault rifle. I can find anything as good. Slow shooting high impact with a good mag and great stability. Love that gun. If I ever do upgrade i won't be dismantling it. I found a level 20 blue rifle that was even better except 21 bullets was long enough.