Performance
Regarding horsepower, the Mercedes-Benz R-Class packs quite a wallop and will knock the BMW 3 Series down a few rungs. However, note that high horsepower engines often command higher insurance premiums.
Handling
The Mercedes-Benz R-Class has markedly bigger tires than the BMW 3 Series. Keep in mind that wider tires can improve handling, while smaller tires could provide better handling in deep snow.
With their similar turning radii, the BMW 3 Series and the Mercedes-Benz quite certainly handle approximately the same into and out of tight spots.
Drivetrain
The R-Class has a bigger engine than the BMW 3 Series. Note that smaller engines are often cheaper to fix, but smaller engines can be stressed more.
The 3 Series could learn a lesson or two from the R-Class as far as torque.
Torque equals pickup, and the Mercedes-Benz R-Class will have picked up and gone by the time the BMW 3 Series finally gets moving.
Utility
The Mercedes-Benz R-Class's more sizeable trunk will accommodate more sizeable objects than the 3 Series.
Drivers with frequent kid-duty might favor the Mercedes-Benz R-Class over the BMW 3 Series.
Dimensions
The Mercedes-Benz R-Class is quite a bit heavier than the BMW 3 Series.
Your wallet will hurt more every time you fill up the Mercedes-Benz than the BMW 3 Series because of its more capacious tank.
The BMW 3 Series fits in smaller parking spaces than the Mercedes-Benz.
The BMW 3 Series's shorter wheelbase will give a sprier feel in daily traffic. However, the Mercedes-Benz R-Class is likely to have a smoother, more stable ride.
Cost
The destination charge is a standard charge for transporting the vehicle from its point of origin to the dealer. It costs approximately the same to get the BMW 3 Series to the dealership as the Mercedes-Benz.
The BMW 3 Series is substantially less expensive than the Mercedes-Benz R-Class regarding MSRP.
Overview
The Mercedes-Benz R-Class and the BMW have the same basic warranty.