Be carefull about packing those bearings on w210's.
I have had 2 clients do it themselves and remove the original
MB grease. The bearings failed shortly thereafter.
We have no set service interval for "bearing service" since you
do not need to remove the hubs to replace the rotors like on the
older cars.
I was told bearings are service free. ( just like the .6 trans, yikes!)
I know we don't even stock the grease seals.
I have done the bearings on my E55 and E300 without harm, but
I had to get the O.E. bearing grease from Mobil Germany.
It was Mobil SHC220 "Mobilith Synthetic Lubricating Grease".

Good luck and have fun.
Dr.D