There are many places you can buy ASICs: BFL, KNC, BitFury, ASICMiner, Avalon clones, and maybe a few others I'm not sure are scams or not.
There are 4 big factors: Price, Speed, Power Consumption, and Lead Time. Each manufacturer has their own pros and cons.
ASICMiner has the absolute lowest lead time, but their prices, speed, and power requirements are pretty crappy. BFL's Monarch is the opposite: it has great price, speed, and power efficiency, but the lead time is a bitch.
I know BitFury is now shipping, and customers are mining away with their devices. I don't think KNC has delivered anything to-date.
If I were choosing, I would go with BitFury, or if you feel like taking a risk, go with Monarchs.
You forgot:
http://cointerra.com/shopCurrently available for pre-sale are the TerraMiner IV 2TH/s mining rig and packages of GoldStrike1500GH/s ASIC chips (with price points for 10 and 25 TerraHashes). Please visit our shop for more information.
TerraMiner IV
Mining Controller with Ethernet Connection
Uses 4 GoldStike1 ASICs for 2 TH/s performance
Estimated Power Usage 1200 Watts
Buy a 5-pack and save
GoldStrike1 ASIC Packages
500 GH/s ASIC
Estimated Power usage 0.55 watts/GH
Sold in 10 and 25 TerraHash Packs
Larger Packs Available, Please Contact
[email protected]GoldStrike1 (GS1) is a 28nm chip with a 0.5TH rate and power consumption of 0.55 watt/GH.
The GS1 chips and products are expected to ship in December 2013.
For any undelivered orders in Batch 1, if CoinTerra changes the price of TerraMiner IV systems or GoldStrike1 ASICs before delivery, CoinTerra will re-price all orders and offer either a cash refund or a larger and more valuable hash power credit
Chances are slim, but if we do not deliver your confirmed December delivery within 30 days of our promise, we will credit your account 20% of the hash power.
I would probably order from them instead of BFL Monarch. In fact, I would never order from BFL.