Took BEC today; no clue how I did. First testlet was fine, 2nd was definitely harder.
The problem with BEC is that it is so broad. You may have a little knowledge about a lot, but it's hard to have a lot of knowledge about a lot. This is what makes the conceptual questions more difficult. You may have a general knowledge of the concepts/terms but because all of the answers dance around the true answer, it is really hard to know the correct answer … you have an idea but the options all seem similar. This is because, again, because the material is so broad, it's hard to know a lot of detail about a lot of details.
Becker was fine. Was pretty much in line with the questions, particularly the math intensive ones. However, I think Becker doesn't do the best job at emphasizing both math-related and conceptual non-math related information equally.