What tires did your come with from the factory? Maker, model and size. Are MO tires worth it?

It depends on the trim and wheel package your vehicle is.

For mine, ‘12 e550 coupe with 18 in AMG wheels the fronts are 235/40 and rears are 255/35. The original tires are Michelin Primacy MXM4.

I recently posted about replacing with Continental ExtremeContact DWS06 Plus tires and widening them to 245/40 in front and 265/35 rears. The change has been a much more comfortable and smooth ride (way less bumpy that I felt all the time) and hopefully no more tire bubbles (had 2 with the Michelins).

https://mbworld.org/forums/e-class-c...lin-tires.html

I did notice going on exit ramps and giving it some more speed on the turn it does seem my traction control is kicking in more. I don’t know if it is because I am really going faster, the wider rear tires, or the rubber of the Continental but I did notice this. Other than that it’s performed better than the OEM Michelins. Being RWD it can be a bit loose in the back.

I've noticed that tire places often inflate the tires to the pressure for full load. Since we're not usually carrying four people and suitcases, a lower number can help with rear wheelspin.

I will definitely reduce the psi in my tires, you are right that they are inflated above where they should be. That should help the rear grip.