Be careful what you are asking.....
Easy math ( not exact, just easy): $15,000 = 150 btc. 400 gh/s = 15 btc / day. Break even = 10 days.
I'll take 10 please.
Ask me when 400 gh/s = 1.5 btc and I'll take zero.
I'll second that - if you can deliver 400ghash now (as stated in your edited original post) I'll take one unit. Deliver next month and I am less interested, deliver in July or August and I'd probably get better $/hash from dyi asics or maybe/possibly BFL in stock items...