I'll make it short and sweet ... While I can't justify the cost of the extreme premium cards like the Matrix, Classified, Lightning, etc, because the cost increase comes no where close to covering the cost increase, I would never, ever use a reference card. Buying a non-reference card has, to date, been the proverbial "no brainer". So lets take that right off the table.
As for making a choice, I never make recommendations based upon speculation on how a card is 'expected' to perform. So until the 19th when we see actual performance data, everything is pure speculation. However, w/o you stating a resolution, the appropriateness of either choice is in question. Nvidia said the 1060 was faster than the 980 (and I bet it was ...
in the metric they chose) .... but leaked test results piuty it much closer to the 970. The 1060 is expected to perform between a 970 and a 980.
I'd put the reference 1060 at about 50% faster than a reference 770, until we know more.... the reference 970 was 43% faster than the reference 770. The non-reference at stock would add about 5%.