For those of you who are knowledgeable about the UOA's, what is the real risk of "break in" metals in the oil during the first few 1000 miles of an engines life? I understand the concept, a brand new engine will break in and rings will seat, metals will shed, etc. My question is, how dangerous is it to have these break in metals in the oil during the first few intervals? Yes I know some advocate for an early oil change to get the metals out, others do not. opinions? Thanks.