looking for a bit of a confirmation on a build before I go out and throw down $2000+ on it:

MSI Z87-G45 GAMING  ($160)
2*600W power supplies (full 600w on 12V) ($40 each BEFORE a $15 MIR)
cheap celeron processor (about $50-70)
2x2gb ram ($40)
6x Sapphire R9 270X dual-x  ($240 each)
6x usb risers ($25 each)

USB w/ BAMT
keyboard
mouse
monitor

Does this look like a good build? Ive read the sapphire cards can be pushed into the 450-480 khash range, so 2.7Mhash/s for about $2250. ($0.80/khash) I plan to use either a milkcrate or a shoerack and a few zipties to hold everything in place.

My biggest concern is of being late to the game. scrypt ASICs are close, and will offer about 1/10th the power draw. I expect these to roll-out on a large scale in the next 2-3 months. The GPU rig would require about 6-9 months to break even - maybe 3-4 months if mining doge, having BTC value rebound, and considering a 50% resale value on the components to gamers.