Received my batch 1 miners yesterday.
Realistic guesses please: how likely is it that these devices will actually ROI at some point and how long would it take to make at least some profit with them starting from today?
If ROI is your only goal at this point leave everything you mine in BTC. So if you mine let's say your first 1 Bitcoin and its worth $600 and you leave it alone and Bitcoin goes up to $800 per Bitcoin you have just increased your payback for the same amount of time by $200. But if you mine for a week and move it all out to USD then you have a return at that days Bitcoin rate. So if you think Bitcoin will rise as I do, leave it all in BTC until you see that your conversion to USD is the same as what you paid in dollars assuming you paid in dollars. Also you will have to factor in electricity.
Right now with Bitcoin dropping in price its hard to feel any of these units at the prices we are seeing will ROI.