Mini vans are pretty safe....here are the crash-test ratings for four year old minivans:
http://www.safercar.gov/portal/site/...002fd17898RCRD
Lot of five-star ratings there. I couldn't find anything for a 208 CLK, but the 2003 C Class, of comparable size, has a four-star frontal (a Toyota Sienna minivan has five). So they're not all that bad....
Now for some physics. The force of a body in motion is known as "
kinetic energy".
It is equal to mass times velocity squared over two. The velocity squared part is why a 50 grain .223 rifle slug will turn one's insides to jello, where a 50 grain .22 rifle cartridge, same mass and diameter, won't do nearly as much damage, ditto for .44 S&W vs .44 magnum, .38 special vs. .357 magnum, etc etc... And it is the energy that basically tears a vehicle to bits when the vehicle is in a collision.
As mentioned, kinetic energy increases with the square of velocity (i.e., speed (velocity) times itself...10 squared is 100 for those who dozed off in math class
)...so speeding up from, say, 60 to 120 mph doesn't double the kinetic energy, it
quadruples it.
So if we take a 3450 pound CLK55, add a 175 pound adult male and two 50 pound kids to get 3725 = 1690 Kg, and run it at 110 mph = 49 m/sec, we get a kinetic energy of 2,049,071.76 Joules (which equals 1,475,124.35 foot pounds, or in common terms, a sh!tload), as opposed to 951,686 joules at 75 mph.
A 5000 pound minivan at 75 mph has 1,277,008 Joules. I'd prefer to be in a 5-star minivan in a 75 mph crash anyday. Its 5000 pounds of mass is going to survive 1.3 million Joules' worth much better than the CLK's 3700 will survive 2 million.
So for me, the rule is, kid in the car, I drive 70 tops. It's not worth the risk.