The ML has seemed to have some different brake wear. The unusual part is the rear brakes seem to last only a little longer than front. The rears usually last twice as long.
On most MBs that means about 20-30k on the front and a double that on the rear.
My wife's 98 ML with 32k has had one set of front pads. I think it was about 25k.
The europeans have built a great reputation for handling and brakes using very light equpment. MB pads are half the price of Honda pads and their rotors are about the same if bought by the pound (An E320 front rotor is probably twice as heavy as an Accords)
Bosch Master, ASE Master, L1
33 years MB technician