Simple, answer is none...
Guess the good old days of mining@home have come to an end...?
Nothing "comes to an end". There is a lot of risk right now. Prices are still relatively high, there is a massive amount of yet undelivered pre-orders, difficulty is exploding, and you would be at the end of the line.
However in time prices will come down, difficulty will be more predictable, and backlog of orders will be reduced. The gold rush days are already gone. You can purchase today likely taking the maximum risk for the smallest reward chasing the gold rush days which are gone or look to the future when you may be able to make a solid but small return with less risk.
