https://siamining.com/addresses/6710f834c7c5d4ee5b4f41fe7b0a37602c0e625580bb13e0e06cfd411e4fd1ee490910378795192 days roi, linear values (and pretty unrealistic ones), a bit different from your math. But anyway, it's not important. Let's build, not destroy

yeah and you can tweak it to the unbelievable level of 80-90w for 30MH, just decrease the core and the power limit and increase the mem
no other card can match this result at the moment, i'm still laughing at those saying that 1070 was trash in etheruem...
Give me a few more days and i'll probably be able to do 30+Mh on my 480 at 100watt if not less.
And that for almost half the price ;-)
I'm pretty sure that you could make it, wonderful job with the other nano's.