I am leaning more and more to pre-cuts, not only for safety reasons, but because I can't stand for long periods of time and cutting out a quilt has become torture, not pleasure. And I do take breaks, but they get longer and the cutting time gets shorter. I do cut sitting down, but the angle is awkward.
As long as I know they are cut correctly (so far, I've found that RJR, Robert Kaufman, Moda are all good), and I find something I like (especially if it's on sale), I don't worry. Honey buns (1-1/4" strips; Kona Cotton and Bella) make great sashing, and jelly roll strips make great borders and binding.