I find the dealers here in Southern Calif to be trustworthy but expensive. I asked exactly the same question as the OP regarding preventative rod bearings and was given the same answer and the same rough quote...and that was 5 years ago at 76k miles. Orig RBs are still in there. BMW labor prices are high as are their OEM parts costs and the costs of their overall investment is shockingly massive. But I knew that going in. Besides, for what other make of exotic car can you find bargain dealership service? Bashing the dealer is useful for creating lively conversations but I understand the dealer business and I find the technicians to be responsible, good and proficient people that are forbidden from doing what indies do.