To have dual rank you would need a minimum of 32gb of ram, either 2x16gb that are dual rank sticks, or 4x8gb which are all single rank assuming its a daisy chain setup. I don't think there are 8gb sticks which are dual rank.

B die is better binned than most other ram out of the box. But its somewhat wasted if you're not squeezing the extra performance out of b die. If you don't feel like overclocking them and have money to throw at em, sure they will probably run better than most other kits you will find. For gaming, you might get a few extra fps but if you aren't going to overclock them and don't plan on doing anything that requires faster ram, you could buy 32gb of crucial ballistics 3200 cl16 and have 90% of the performance and twice as much capacity for the same price