i took the boards in feb 2004. it's been a while...but i think i studied the valley review...nothing else... other than what was required for the comprehensive exams for school of course. i probably put in 8 weeks or so....(i didnt attend the valley review, too expensive... i just coppied the study guide from someone).
the valley review specifically prepped me for the board exam. 75 questions...in and out. keep in mind, the tougher the questions, the more likely you will pass.