BTW, have you put any thought into reflashing the kk2 board?
If you haven't, you really should. Stock ROMs from HK are abysmal. The open source ROMs (Steveis, RC911) are far superior. you will need some hardware to reprogram an Atmel chip, with a USBASP as the usual suspect. An Arduino can do it as well, but you'll have to hunt down the sketch to drive it. (there is an example sketch that has been reported to work, but anyone I personally know who has tried, hasn't succeeded and switched to a different interface)
The best software to drive the flash process is the kkMulticopter Flashtool, and it lists the variety of programing hardware it supports, along with a repository of ROMS it can reprogram on various boards/ESCs.