For stability testing I like y-cruncher. It teases out edge cases that many XMP profiles are unstable with. I'd take a slightly less efficient system that I am confident will not error.
Also, those numbers aren't far off the out-of-box behavior I had, but I like to tinker. I throttle with PL set to 190 but not at 180.
I've been experimenting with different settings and found that unlimited PL2 and undervolting the CPU by -150mV give the best temperature to performance at ~80c during full load. It has been running stable for few days, and I'm pretty happy with the result so far.