I have the same car as tkamiya, with the same M104 engine, and mine runs at exactly the same temperature in hot, Southern California weather.
In more moderate weather (65 - 80 degrees F), I run 90 to 92 degrees, and may go up to 95-98 degrees in stop and go traffic.
When I went to Las Vegas a couple of weeks ago, it was in the 90s, and I was consistently at 100-102 in stop and go traffic on the strip.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".