There is only one coin to mine and it has issues, 10K international + 6k china units sold and new batches coming online.
ROI for first batch of internationals will be $30/day maybe $50 for a short time. My D3 is doing almost as good as the L3+. The A3 wont even come close to the lifespan the D3 will have.
Only one coin that is very profitable to mine at this moment with the A3. Well, in fact there is another Blake2b coin, but I have not made calculations.