The 480 should last you a good 2 years at least with a decent resale value. You should be able to pass it on to someone else and get some cash, then use that to upgrade to a better card.
I cannot say the same for the 1060, so between these two I went for the 480. I don't want to be stuck with a 1060 two years down the road, when DX12/Vulkan are the norm.
On the other hand a 1070, or even a 980ti simply have the raw power to outperform the 480 even in DX12/Vulkan. So it's all relative...
In the same manner, even a 390X will stay relevant and outperform the 480 for sure...
So it's all relative. If you want a new card with HDR, new hardware codec support, etc, then the 480 is probably the best buy.
If you just want good frame rates and don't care about such things a 390X nowadays is better value (and usually bundled with some nice game).
+1 for the above if you have a FreeSync monitor.
-1 if you have a G-Sync monitor, in which case a 980ti is very good value. In this case, if you can afford a 1070 you're golden... It'd beat the 480 even in DX13 or DX14 years from now base on raw power
The only card I can't justify buying is the 1060... Too ephemeral for my standards...