I have not seen any oil consumption issues with the 104 yet. They have been really durable. The reason they don't wear the guides like the 103 is because of the geometry of the head. The 104 uses a cam over valve design. This allows the valve to be pressed on straight down. The 103 has a rocker set at and angle, this pushes side pressure and allows for some wear.
1992 500E (very soon I hope
1981 280GE SWB
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