Break-even Exchange Rate for Miners?

[nodroids]

So, what is break-even exchange price looking like to you small-medium, but fairly pro miner, if you buy the best chips on pre-order? Break even in March assuming doubling of difficulty every month?

 I'm a non miner and my ignorance based calculations suggest that if you're buying the top chips on pre-order, like a Jupiter, then break-even exchange price is roughly $1350 for you small-medium, but fairly pro miners come February-March, presuming doubling of difficulty each month. Really I'm asking because I'm just a trader of all my families' new fiat into BTC as we get new fiat savings. Your guy's reality is a big part of the puzzle to supply and demand...

[traiz]

It depends on what you believe the difficulty is going to be, and your plans for BTC.
For me, its a hobby (got me out of some MMORPGs I've been stuck in for years).

Let's suppose I brought a November KNC Jupiter (for $5000 USD) earlier this year - hashing at around 680 GH.
At the current difficulty, 1180M, it will earn around .28 BTC/day.

If the current difficult stays 1180M for 30 days, before doubling, I would have 8.4 BTC at the end of the month (on Jan 1)
Next month, it would earn .14 BTC/day, at the end of that month - 4.2 BTC (on Feb 1)
and 2.1 march 1.
For a total of 14.7 BTC. So following your assumptions, break even would be around $340 per BTC (not counting the energy used to mine)


However, its more likely that the difficulty goes up 30% every 12 days....