I love the big Robbins. In fact I love it so much that I tried reading it cover to cover for boards. I TRIED, I sure did. I heard all that nonsense that memorizing robbins is enough to do well on boards, and I believed it. . .at first.
I had about 10 weeks to study for boards. After three weeks of intensely reading that monster for 12 hours every day (against everyone's advice), I managed to plow through a total of 9 out of the 32 chapters. My brain was totally fried, AND I realized that even big Robbins does not cover a lot of what you need to know for Step 1.
In fact, at the end of those awful 3 weeks, I went back and started studying for boards from scratch, using the review books like most of my wiser classmates were doing. When I got to my pathology week, I read BRS path cover to cover, and MANY of its topics were not even mentioned in Robbins, and let me tell you, even BRS path does not mention 100% of topics that Step 1 might cover.
All in all, I am sadder that I wasted those three weeks reading the first 400 pages of Robbins that I could have used to learn pharm or anatomy better, but wiser, in that I realized that Robbins is that long mostly because of the prose.
Don't make the same mistake I made. I say buy big Robbins to use as a reference book, or (if you med school doesn't give you lecture notes to study from) to use as daily reading for studying during your path course. But whatever you do, DON'T use it to study for boards (except for reference).