Just want to chime in, I have an 8700k, the Prime A, and a Cooler Master evo 212 (pretty much the same thing) and it works fine if you are not overclocking. ... ,
however I am at 4.8ghz (-3 avx offset) and 1.22 vcore and getting around 35c idle and 85c load right now. About 90c if using Prime95.
Intel i7 8700k cooling solution