Go for the 1060 6GB, works out the same price as the RX 480, is better optimized and performs 10% better.
@jeffreddo, no point upgrading to crossfire RX 480s anyway, scaling isn't great and it'd be a waste of cash really.
I wouldn't consider SLI even if it was available with the 1060, only with the 1070 and up does it become truly viable imo.
Comes with a free mouse for a time:
https://pcpartpicker.com/product/7RKhP6/gigabyte-geforc...