Link to buy:
The M71 Quadcopter has a unique design that makes it look like a tricopter. Its 2 front motors are located in a protective sphere at the front of the frame. This creates a sturdy, well protected bumper that has been very resilient to crashing. The problem with this is that it doesn't rotate on the quadcopters center of gravity. This means that when you add yaw (spin the quad) it tends to drift slightly in a unintended direction. It's not as noticeable outside where you have more room to fly around.
I didn't expect flips to be very smooth, but as long as you have around 5 feet of altitude, the M71 quadcopter does side flips and back flips. For some reason mine didn't want to do front flips.