Besides gaming I am looking at this for video rendering and most software like Premiere takes advantage of multi GPU as well as thinking can push more pixels for 4K gaming.
I am concerned about heat and noise though as extra load on system and requiring a 750W power supply ups the factor.
Considering my last build was in 2011 with sandy bridge and a minor GPU upgrade about 2 years ago, I think a 6 core with 2 GPU will get me another 4 years.