Choosing between DDR4-3200 2x8GB or DDR4-2666 2x16GB

Thanks to the RAMpocalypse, I'm currently debating on going with either 16GB of 3200mhz memory or 32GB of 2666mhz memory.

What would be the better choice in this case? I can spend either around $70 on a 2x8GB kit or about $120 for a 2x16GB kit.