I did miss it
(or I forgot it, I read so many posts per day
)

I wouldn't mind getting doubles of Descent stuff, but I just keep getting Lvl 16 grey stuff from the NM Dragons.
Last purple weapon I got, which I didn't have before, was Sulevin Blade.
Don't really need it (Reaver uses Stonebreaker and Katari/Avvar use Skywatcher's Cleaver), but nice to have. 
BUT
I got it from the store, not the Dragon.
Sometimes he's generous, but store chests much moreso. I couldn't tell you which items I got from NM dragon with about 75 kills, but no hakkon yet. I do know right after a NM dragon slaying me and Ophaus went right to the store and bought a few chests. He got a 27(don't remember which as I only care about myself lol) but I got a Dancer's Axe right after. not saying that to insult you, just saying that this game and the chest purchases tends to be very trendy. As for my own superstitions, I think its best to open 2 2k chests and see if you get at least 1 purple in each. If so, keep buying. If all greys and blues, save your money and try again at another time. Haha, make sure to rub your belly, pat your head, and chew bubblicious at the same time :-)
But, to add insult to injury, got Rime yesterday. However, people tell me its rather ineffective vs. Bitter Axe.
Edit: "She's generous."