I'm surprised that this is not faster than the majority of the competition. Perhaps as you note, that is because of the SSD 960 series being so strong.
I wonder if the PCIe x8 version would be slightly faster. They say 6000 MB/s sequential read and 1,000,000 IOPs random read, so it is certainly possible. No improvements on the write speed though. I would love to see a SSD someday overtake the PCIe 3.0 x8 limits though (that Samsung isn't too far on the sequential though) - we may someday need a PCIe 3.0 x16 SSD!
It is also likely that this is a TLC drive. All of Samsung's other "PM" drives are TLC, while the "SM" drivers are MLC. Still the PE cycles at 40nm 3D should more than adequate. Maybe an MLC drive would do better - both in endurance and performance. The difference should be comparable to the 960 Evo to Pro I'd guess, provided they both have the same percentage of overprovisioning.
Overall, I'd say the Huawei ES3600P V3 and the HHHL ES3600C V3 are the top SSDs.