I stays as I do since 1.5 years. Cant decide to buy GPUs. Dont know really, ROI is too high for a long time.When I bought my 1070s, ETH roi was 5-6 months(electriticy except). Now, terrible times.
When I bought GPU for mining, the ROI was about the 6-9 months. Then the coins price rose a lot, the ROI became 3 months.
more mining they hold much price rocket....the unique we can mine altcoin then sell when that coin long roi....so strategy is key~