i can't get my hand on L3+ now try to buy the A4 dominator 280mh/s with 3000usd i have free electricity
what do you think
If you really do not pay any electricity, you can run them until they break down. It depends on your price. Use a calculator, see what you will earn each day and decide if you can break even.
I personally would not buy an old A4
i can get S9 for 3500 at this time but it's not profitable as A4
the L3+ is sold out in 20 min
what do you buy at this time for next year mining ?