Ah!! good point about the radio gyro mode switch...the gyro needs to be in Heading Lock when you connect the power...dont move the heli for the first few seconds either...the gyro will be sorting itself out in that time.
A good routine is when the power is connected...Always switch the radio on FIRST..and switch off LAST...otherwise the heli could start up and get broken...or fly into your face
So be careful.
Another good point is before you power the motor up to fly...just wiggle the sticks and see that the cyclic works...wiggle the tail control too...make sure the gyro hasnt taken a sulk and locked itself up...happened to me once with a Trex 450...I lifted off and did a quick piroutte before it hit the deck.
Make sure to check all nuts and bolts...check the whole thing over...watch for loose wires...they can get chafed very quickly and then fail.
Rob