My full-time, factory trained MBZ Lead tech friend constantly nags me to have him roll in a new chain-my '92 500E has 94k miles. I plan to do it at the end of the summer.
Unless the car's been on Synthetic changes every 5-7k miles since birth, and you have the documentation to prove it, I'd pop for a new chain & upper rails-reasonably cheap insurance, as the job should cost less than $1k parts & labor.
FWIW-if the chain lets go, and this is indeed fairly rare, you're looking at large to HUGE dollars
"If everything seems under control, you're simply not going fast enough" --Mario Andretti
1995 E500 street car
1986 Porsche 944 Turbo S track car