First of all I would like to thank all the members of this forum for contributing their experience for taking  PMP certification. I started my preparation long back but was not concentrating much then I became more serious and did 5 months of normal study ( 1 hour a day ) and 3 weeks of intensive study of 5 hours a day , I used only Rita 6 and no other book even not the PMBOK because I left it was a bit hard to grasp its contents but Rita 6 was very descriptive and easy to understand and never the less FASTrack questions were excellent .