KnC is for sure legit and they collected enough money by pre-orders in June to realize their advanced 28nm ASIC, which will be the base of all their mining devices.
Due to the cooperation with ORSoC there is most likely enough technical competence to do the ASIC front-end design (RTL) and all the additional PCB and software stuff needed for a complete mining device.
They demonstrated that by a FPGA-based prototype called Mars.
I assume there is another partner which is doing the physical implementation of the ASIC, which means transferring the RTL to a technology specific chip layout, which can be manufactured in a foundry like TSMC or GLOBALFOUNDRIES.
So far all fine!

But I strongly doubt their delivery date in September/October, because at their open days beginning of June they said, that they are still about selecting the foundry for ASIC manufacturing. That means that at this point the physical implementation of the ASIC was not started, because this work is very specific to a dedicated foundry, you can't start it without knowing which concrete 28nm technology to go for.
If you have an experienced team, this step alone requires 1 months for an 28nm implementation, if you do it "fast&dirty" and all required IP (standard-cells, IO-pads, PLL, ...) is in place.
The initial mask preparation and manufacturing of the wafers takes about 3 months for 28nm (I doubt that they will get a fast run called "rocket" from TSMC or GF for such a low volume product). They have a very complex package (huge BGA with 2048 pins). So I would estimate that it will take about one months to get the manufactured dies in the package and at the miner PCBs.
In sum, if they selected the foundry mid of June, they will have the first miner prototypes in lab for debugging mid of November. If they are really good and lucky they may start shipping right before Christmas.
If they have to do a re-spin of the ASIC manufacturing (the risk is high, because of the advanced technology node, huge die size and the short development time) there will be nothing before March 2014.