the best gpu ever, personaly i prefered RX5**and RX 4** is the best grafic card and profite
100% depends on what you are mining. My 1080's(each) will mine more the $$ than 2 RX5870 or 580s mine and costs less than 2 RX570s or 580s so its not econimally intelligent to buy 2 rx anything over a 1080 UNLESS you have to mine a specific AMD friendly algo for whatever reason.