I've had a Rockchucker for 40+ yrs, still makes good ammo, no issues with concentricity or CBTO, yet, it's been used and abused enough, it probably should have some form of issue. I've heard of bore wear on alum presses, and linkage slop on some steel presses. heard of one Hornady steel press have bore wear issues. The odd casting breakage on RCBS handle castings, Lee also, Summit press has a weak upper casting, FA M press has inadequate screws on the jaw plate holddown, some inadequate machining clearances on jaw holder castings. As to how to hurt a Forster/Bonanza, only thing is the jaws, you can actually damage those screwing dies down too far, haven't done that yet though, haven't heard any complaints on it, so, not a common issue as far as I'm aware.