My advice… pre-order Butterfly Labs 28nm cards (300GH/s for $2,800 or 600GH/s for $4,680.00), then use the rest of the money to start cloud mining in the meantime. I run CEX
https://cex.io/r/1/magicmustang/0/ which is free to sign up and you pay market value for your GH/s. Check it out…
If I were you, I would stay away from BFL.
They just had too many instances where they didn't keep their delivery date promises.
So by the time you get your device, the gh might be too low for the difficulty that you probably won't get your invested amount of money back.
Also, cloud mining on cex.io is almost useless.
Their price per gh is too high...