The R7 isn't in my system anymore, and the Vega 8 is a little more impressive on paper (more shaders, more than double the memory bandwidth, etc).
Now, I've posted this twice already, but this is where I got my original info:
http://gpu.userbenchmark.com/Compare/AMD-R7-260X-vs-AMD-RX-Vega-8-Ryzen-iGPU/3151vsm441833
I'm just floored that a GPU on the CPU is still so...awful. I thought the idea behind the "APU" was that they could make it faster than a PCIe card. Otherwise, what's the advantage of an APU if it's no better than an iGPU on the motherboard?
EDIT:
As I was doing some more research into the difference in specs, I found multiple sites reporting hugely different comparisons.
Game-debate shows a much faster clock and a lot more shader units than
hwbench for the same Vega GPU. My initial impression of the RX Vega 8 may have been exaggerated by incorrect information.