One: When flying close to the ground you are often in a ackward position as far as ever recovering flying speed

Two: Many of the so called popular 3D planes essentually quit flying when the engine quits and there is nothing you can do about it.

Three: Many of the popular designs cannot land with no power without tearing the gear out from under them.

I've seen all this happen in the last 10 years. I take note of the planes involved and have made it a point to never own any of the types in categories 2 & 3