Some of the very early production KingCats had some boom problems...ask me how I know.
I cracked one boom almost in half one day *(about 2004), and was very lucky to have landed the airplane without further incedent. I replaced the booms, and later repaired the damaged one.
BVM came out with an A.D. that added the carbon fiber patches to the exterior of the boom skins, which solved the problem.

The current production booms are strong enough to be used as crowbars, but there is no sense in subjecting the airframe to high stresses....keep the speed down to a respectable level, and hold the "G's" down.
Buck has good advise on the topic, and I would listen to it and observe it to have a long and happy airframe life.

Mine is flying with a JetCat Titan, and on Sunday, my spotter (BV) and I decided to turn it down from 123,000 to 119,000 RPM, because it is probably doing over 220 MPH at 123,000. These things are pretty clean, and speed build up occurs rapidly...especially when the sharp end is pointed down hill.

Not to rag on, but they are watching us....no event or club field is transparent or hidden from the feds watchful eye. I'm off the soapbox....