I passed BEC the first time with a lot less studying than I thought I'd need. The key for me I think was going to a liberal arts school and having taken a ton of economics and finance courses (I am a triple-major in accounting, finance, and economics).
I used Becker and thought that it would be deficient. I know that the cost accounting section, in particular, would have been extremely challenging to follow for someone who had never taken cost accounting (since it is an elective at some colleges, including where I go). I even found some of the sections incredibly hard to pick back up on (e.g. overhead variances) after having not done a single day of cost accounting in the two and a half years since I took the course. Luckily for me, my exam was heavily weighted in subject areas where I was strong. Maybe I just got lucky – I really don't know. However, other than a few pretest questions (which seemed more appropriate for another section, to be honest), I thought Becker covered all the topics sufficiently. Unlike some, I didn't get any off the wall questions in IT (in fact, mine were so easy, I could hardly believe they were even asking them).
Although I've never tried it, it sounds like Yaeger might be worth a shot if you've never had exposure to the concepts (other than in CPA exam review) and Becker isn't working for you. However, there were some taxation and law concepts I never had before when I was studying for REG, but I read the material in Becker, studied, and studied some more and pulled off a 96 on the exam.
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