<p>CD/DVDs can be problematic, so don't rely on them as fool proof backup media. For one thing, Sanford is running a Mac, and Apple is fazing out optical drives, which means that one would need an external optical drive. This is the same path that floppies went down, it's a dying choice. </p>
<p>TM is good for keeping various versions of files, but fills a drive faster than a cloned drive would. For one thing, TM only copies changes as Sanford said. but it keeps the old versions too. When backing up using a clone it only keeps the changed version, a huge difference in how each works. </p>
<p>I use both TM and make a bootable clone using ChronoSync. If I could only have one backup drive it would be a bootable clone. YMMV</p>