I used it, found the disclaimer about answering 50-60% correctly as being "highly competitive" and to not be discouraged by it pretty interesting. It probably goes a bit more in depth than the actual step 2, but you know, that's gonna vary from question to question. I had a chance to look at a few questions from kaplan and in comparison, found it more challenging. but that's just a personal opinion. bottom line, i don't regret using it.
hope this helps.