Did you use the search feature for "bent rods"? There seems to be no consensus on why this happens but regardless, the factory is supposed to have stronger rods but they never officially admitted the problem and I don't believe there is a distinct p/n for an "improved" rod.
Someone said that they thought the pistons get a layer of carbon on them from leaky turbo oil seals (or worn turbo bearings?) and that reduced the volume raising the compression ratio or something?
cyl #1 has intake that is positioned to allow more crud or water to pass if the headgasket leaks, etc.
Lots of theories on this.
I would use the car and listen carefully to any noises, etc. that might indicate something is about to "happen" and catch it before it does any serious damage, I figure most people that have had this problem were not carefully attuned to their engine, like who would expect the engine in a $50K car to just blow up suddenly for no reason?

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!