When there is no detonation or interference...they last as long as the rings seal. Magnums are hyper...as well as many chevies and others *that are fuel injection. The pistons are high silicon , brittle and conductive and don't grow much at all..hence the rings butting because they are steel or iron and do grow a lot absorbing the higher than average piston temps. I use them in my 340. Many thousands of miles. I've had them shatter in other motors, yes. I wouldn't recommend anyone running them with edgy compression and a carburetor unless they're tune savvy.