Color shift aside, rendering to an image sequence is prudent when a) your computer is acting up, or b) you have a really huge and long render, and if you need to re-render because of a glitch, you can just re-do the errant frames, automatically replacing the originals in the sequence.
And re-rendering the sequence to QT is really fast, since there are no effects or animation to slow things down.
TGAs can be uncompressed, so no quality loss. Then, when you have to store the sequence, you can ZIP/stuff it.
But for most stuff, I just render to the QT codec appropriate to the project.