Thanks for reasonable people's support and also thanks QuestionTime for a debate to make things clear. BTW, QuestionTime made a big mistake to challenge us instead of other agent to sell copycatted miner since JTminer is the original .

A lot of information come out, let's do a summary:
1. dimension: 426*380*200, smaller size than other miners.
2. Can do overclock.
   i. extra power supply can give you the ability to over clock. The boards are equipped with 32+A current capacity power supply per chip:), in 25G/s mode, it only consume 20A per chip. so it has room to do the over clock.
   ii. Linear Tech power supply + careful design gives the ripple only at 20mv:), it will stabilize chips using the higher clock without too much HW error
  
   Kind reminder: For those who bought a copycatted miner from other reseller, please be very cautious to do overclock, it will burn the chip and board.
3.  JT miner spend lot's of effort in the firmware and Pi side. they use the ST MCU. the firmware is written from 0. after JTminer use the ST MCU. some vendors' solution seems to have interests in ST MCU too:)
4. The Pi board can drive up to 8 boards (in lab we do), and each MCU to control the two SPI high speed chain. in this way, give the whole system more flexibility and scalability.
5. We do not have authorized distributor now. Only a few sample units are being sent out.
6. The order for 1200T is to be completed soon. We also have chips in stock for future business.
7. Video link http://www.youtube.com/watch?v=86hZGZAMUHQ‍

Related posts:
https://bitcointalk.org/index.php?topic=470386.msg5564356#msg5564356
https://bitcointalk.org/index.php?topic=470386.msg5561528#msg5561528