hi,
a freind bought a x600d from cnchelicopters.com about a year back. the thing never flew as quadrotors were still in the development and needed a lot of tuning.
after a lot of frustration in tuning it my freind gave up and handed it to me. checked on google and found that there were problems with the basic board and many had scrapped the original board and using other brands.
hence i too got a kk2.0 board and hk multistar 30amp esc and a power distribution board. setup the board as per you tube and it flew on its first flight. only a little gain reduced to avoid excess wobbling.
will fine tune it slowly.
chk pics.
Great build sir!
your friend will be surpassed to see this bird flaying. :)