Despite the significant performance difference between the 950 Pro and 850 Pro we only see a very minor increase when looking at the overall PCMark 8 storage score. That said, this seems to be the norm for this benchmark program and despite the minor increase the 950 Pro produced the highest score of any SSD in this test.
Although PCMark 8's overall score placed the 950 Pro and 850 Pro quite close together, we see that the storage bandwidth results are radically different. The 950 Pro was almost 3x faster than the 850 Pro with a throughput of 778MB/s.
The Photoshop heavy test was completed in 348.5 seconds using the 950 Pro and while it was the fastest SSD tested, the 850 Pro wasn't exactly worlds slower taking 359.9 seconds.
Finally we looked at the World of Warcraft performance and here the 950 Pro took 57 seconds to complete the task, again making it the fastest SSD tested. That said, the 850 Pro took just 57.9 seconds making the 0.9 second margin somewhat negligible.