I started in the third week of January, and am doing a modified version of dentalWork's study plan since I'm also taking classes (basically split each day into two). So far everything seems to be going well, and I think I'm retaining most of the information. To help solidify everything later on, I make an outline of each KBB/AP Bio chapter on the "intense reading" days so that I can review them periodically.
This amounts to 3-5 hours of DAT work a day, which I do almost everyday. In fact, today is my first real "break" in a long time. The only other times I take breaks are two-three days before an exam so I can buckle down and study. So far it's been working great, and I should be done with the content review period by April 2nd, and then I'll do the Destroyers two or three times, along with CrackPAT, and then follow that up with Qvault, Achiever, and maybe Bootcamp before I take my exam on June 2nd!