my last 2 or 3 batches were terrible efficiency and also came from BMW. but on the other hand, i buy my grain exclusively from them because, historically, i have gotten better results from their crush than my lbhs.
i've blamed my recent poor results on changes in process and equipment. made a new manifold cause i was tired of vorlaufing for 10+ minutes and still seeing grain, but the new manifold is no better (straining through hop bag now to solve that). also started using beersmith, which has recommended strike temps that cause my mash to end up 5+ degrees to high :/
tl;dr: will continue to get my grain from bmw