I take CE in a week and a half so I can give a better opinion then, but I think COMBANK sucks balls for Level 2 CE. It was money for Level 1 but I couldn't stand how poorly written (bad grammar, misspellings, etc) questions are on COMBANK. Their explanations are bad and I felt like I was commenting every time I did a 50 question block. Half the time their explanation is along the lines of:
Choice A - wrong because choice B is right
Choice C - wrong because choice B is right
Choice D - wrong because choice B is right
Choice E - wrong because choice B is right
How is that helpful for studying? I was doing pretty crappy (high 50's, low 60's) on it even though I easily beat the average on every NBME shelf. I'm doing COMQUEST now and it seems to be a better qbank. My scores are more on line with my knowledge as well as my UW scores.
Even though COMBANK has 900 more questions, there are so many word for word repeats in the bank that I think it eliminates at least 2-300 of them. It seemed like every time I did a set of 50, I had two 2 questions sets that were almost identically the same.