Unfortunately it is almost a direct clone of the Marushin, with some internal differences. Same zinc alloy for the important bits so it will probably have the same issues with breaking parts.
I have an M2 carbine that I managed to fix the broken bolt on after several tries- see the thread below.
http://ww2aa.proboards.com/thread/11...crollTo=135344
On the plus side, if enough of the KA carbines sell maybe RA will start making the steel parts again.
Cheers