I trust Moda not to bleed...some day that might bite me in the butt but so far I've had good luck.
I don't pre-wash my pre-cuts...I just throw in a few color catchers with the finished quilt "just in case". So far that has worked for me. I don't buy "no-name" precuts, though; only from manufacturers where I have used their yardage without having bleeding problems in the past. (My "trusted" list for precuts is short: Kona, Moda, Connecting Threads, and Hoffman)