That depends on your conditions, if you're in a cool area and have low electricity rates then yes the R9 390 is absolutely a choice you might have, it still gets (last time i checked) approximately 30mhs on eth, it just draws a lot of power.
Well it will be in my house so 76 degrees on the regular and it cost about .10 cents a kw. And i was planning on mining like Litecoin/Doge, Dash maybe.....and/or eth