You've got to be an "enthusiast", by enthusiast I mean somebody that likes to drop top dollar on a card but not being able to play any of the latest releases with Crossfire enabled
Last time I dabbled with Crossfire it was poor, doesn't seem like things have changed too much.
My experience has been playing many older games with crossfire perfectly fine, just issues with the new ones. Therefore I have come to conclusion that if you are someone who likely to play games on release, multi gpu is not a good idea.
I have had so much fun being able to finally play so many games in 4K because of my 295x2. Even Metal Gear Solid 5: The Phantom pain worked very nicely on release. But not being able to play the Elite Dangerous, Witcher 3 and Fallout 4 in crossfire properly was frustrating.
It will be interesting to see if this liquid VR thing will get proper crossfire day one support.