Yeah, if you're going to go with 1070s I would definitely wait for the price to come down, but people are trying to dump their 980Ti/TTX GPUs for pretty cheap, so if you want to grab something like an EVGA card (or some other manufacturer which allows for a transferable warranty), then I don't see 980 Ti SLI being a bad move, since you can likely 5-box at 4K with a few settings turned down to stay under 6GB and keep performance good.
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