Now they are for 0,2BTC each.
will they pay for themselves or its actually a lost cause and not worht it?
even if they were at .2BTC each, they'd never pay for themselves........... unless bitcoin price went up a lot
but then you'd be better off buying bitcoins
the only way they'd ever make .2 bitcoins in their lifetime is if bitcoin price was to plummet & thus cause difficulty level to drop. even if difficulty dropped to 20% gain per cycle, it'd take, what, thousands of years to get .2 bitcoins ?