I just took it this past October and passed. It was crazy hard.
Study everything; the last two weeks, identify your weak areas and dig into them. The test is very intuitive, quickly identifies your weak areas and tailors your test to torture you.
My test was all molecular, complement, and HLA. I had only one calculation and one question about panels. A few of my classmates took the test: one had all donor stuff (her weakness), someone had a lot of calculations (his weak area).
If you can get a hold of the AABB Annual Meeting SBB review, I would recommend memorizing what's on there.
Wishing you the best! If you want any specific details about the format of the exam, etc, private message me.