There are aerocommanders in Australia with well over 30,000 hours on the airframe, most of which are operated at low level and at the increased VFR weights, with no issues.
For those of you thinking this is an inflight break up, where is the wreckage, usually strewn over several kms ?.
From personal experience, the AC50 is a very very well designed aeroplane, when operated normally, is well within its destructive limits.
Just because an aeroplane does not have wing struts, does not automatically make it poorly designed or fragile, how many big aeroplane have wing struts ?.
With most accidents, the cause is a lot simpler than a poor designed aeroplane and/or multiple engineers missing a possible airframe defect...........the most common cause is the flight crew ( historically speaking, most accidents are caused by the pilots, as there is no evidence either way it can not be discounted ).