Thanks for the clarification on slants. I had thought that the hardiness was supposed to be a big advantage for using that method... yay for me not having misremembered.
The true beauty in slant-based storage is purity, that is, as long as the slant was inoculated with a single colony or a slant that was inoculated from a single colony source (i.e., all liquid cultures need to be plated for singles before being transferred to slant). Slants are much purer than liquid cultures because they are propagated under sterile (aseptic) conditions. One thing that I really like about slants is that they can be visually inspected for contamination. Yeast, mold, and bacteria are generally noticeably different looking on solid media. One will know fairly quickly if one needs to work on one's aseptic technique.