Rosebuds right... A few things need to be changed right away on the K2 because the stock parts are really junky. So change the motor to a brushless or outrunner as they are known by and a 25-30A ESC. After that get plenty of plastic spare bits, flybars, feathering shafts etc. So you don't have to wait on parts to arrive so you can keep flying.

I wouldn't get the cnc head and tail until you were hovering without smacking into to many heli magnets any more. Its better to upgrade other things first.

Hope this helps some

happy fly'n