I would like to get a set of 15" wheels for my 03 ML500 for comfort and that beefy fat tire look.

Is there a downside to it?

Any advantage beside comfort?

Is safety gonna be an issue?

I am not an expert on this, but I think you won’t be able to fit the 15" rims. Because of the clearance issues with your Brake caliper/rotor especially if you drive a 500 with bigger brakes, then the smaller brakes of the 320/350. The smallest rim I can fit on my truck is a 17". Check first before you buy.

Thanks. I totally forgot about the bigger brake I have on the 03 & up ML500s. I guess I have to look for other means of getting a more comfy ride for my mom.