If that's what you want, why wait? What is to be gained from waiting? In my opinion, the primary difference between each company would be their warranties, and their reputation for how they handle those warranty claims. That's about it.
The reference 980 Ti, if its anything like my Titan X, is going to hold a steady boost clock around 1350-1360 Mhz, with a +400 overclock on the memory. That's reference, no voltage adjustment.
Furthermore, we're talking about nearly 3000 cuda cores. What difference does a hundred, or a few hundred Mhz really matter? If you have chosen an appropriate resolution and game settings for the capabilities of the hardware, then all we're talking about is a few extra frames over what is likely already...