Yo!
So I've tried simming the new crafted Legendary Waist (http://ptr.wowhead.com/item=146667/r...essant-courage) and I was pretty surprised with the results. I have the Helm/Cloak/Ring but the crafted Legendary Waist simmed highest combined with Helmet. It was about 10k DPS increase and that was the 910 version as it is bugged on Simcraft, the 940 version should be close to a 20k DPS increase.
The main problem with the Helm/Cloak combination is that you have to use the Set Chest and both the Set Chest and the Legendary Cloak don't have haste. Whereas the Set Cloak combined with the Chest from Gul'dan both have haste. The crafted Legendary Waist also has haste/mastery + 3 sockets, and some nice movement speed which can be useful at times.
Will it become 2nd BiS? I think it will, at least for NH with the current set items stat distribution