Hi,
First, I tried to search about this but those threads was closed or very old ones so..
Is this miner still effective?
They are not badly priced and I could get 2 of this for price of 1 s7.
So about 9th/s vs 4.7th/s.
But there is many broken ones or not fully working ones on sale. Are this miners too old for buying?
Should I just buy new s7 instead.
I dont need to concern about electricity bills because someone else is paying it for me.
That someone else might start caring, when that person see his bill going up by 500USD per month. But a SP30 for 450$ would be a good price, no doubt. Not sure just your electric situation is really going to make it work properly.