That very much depends on what you think btc will be worth in the future, and if you're willing to hold on to it for that long. Try putting in $30 as the value of btc, and redo your calculation..
Of course, if the value of BTC rises by A LOT, then yeah, perhaps it could pay off mining, but I doubt it will go above $10 unless we get another surge of popularity like earlier in the year.