I might consider 3 BTC's worth.
What is the expected hashrate for 3 BTC's?

Currently I have on order:
10 Shares via KnC group buy worth 28 GH/s I paid 5 BTC's
7 Shares via KnC group buy worth 9.87 Gh/s I paid 2.1 BTC's
3 K16's via TerraHash worth 13.5 Gh/s for $750 or ~7 BTC's