Since the cause of the bent rods has not been fully determined, there cannot be a point beyond which the vehicle can be considered safe from the problem.

The 3.5L engine can bend a rod at any point in its life. When you purchase one, you are taking an $8K crapshoot.

If you want a lot of steel around you, consider a W126 gasser.........either a 300SEL or a 420SEL. Sure they burn more gas, but, you would need to drive over 100K miles to finally make up the difference in the purchase price. With the cost of diesel fuel currently at 20% over the cost of RUG, you might need to drive 200K to finally break even. The 350SD and SDL make no economic sense.