I'll definitely stick with you guys, but there's still stuttering here and crossfire was hot back in 2013/2014, they put much knowledge into it, so it may worth trying.
I just checked eBay: those R9 280X OC were purchased in Oct. 2020 (for half the price they are now). There were no black skies then, and as you said, this came up round about a year ago.
It looks like someone tidied up.