RX 560's are a good inexpensive low power option for mining ETH. They use about 60 W and if you can get 17 MH/s, that is a very good cost/hash ratio. Increased availability on RX 570/580 from the Vega launch has lowered the demand for lower performance cards like the 560 for mining ETH. I would say you could definitely mine profitably with the 4GB cards before the ETH switch to fully POS sometime next year and can still mine other ETH based clones.