As much as I love to drive the w113, the workhorse of my stable is a Ford F150. Tows boats, hauls appliances and lumber, great reliable work truck. The E500 (5 speed) I own is stylish and comfortable but not reliable. I hope I do not get flamed for this statement, but the newer MB seem to suffer from Quality Control and with the price tag a consumer pays you should not have to worry about the constant electrical problems, tranny issues and numerous service bulletins. I would not own a modem Mercedes again too many sensors, too much time in the shop and major design flaws. The newer 7 speed transmission of the E550 has had many issues from what I heard.
I will say my good friend is over 200K m. on his second MLB. He has to repair it quite often but it still drives well for having 200K on the odometer. I have also heard the 6cyclinder modem Mercs is much more reliable than the V8 although they have known problems as well. I have spoken with former Benz owners that traded their MB in for a LEXUS or BMW and get the same level of comfort but it has the reliability and ease of ownership that many modern Mercedes are lacking but maybe mine was built on a Friday