Sorry for the stupid question. Which output format is a more clear one among all sorts of HD format?
I think you will get a variety of answers, depending on the source format and the planned use for the final video. For example, I mostly shoot with an AVCHD camcorder, so I prefer to output AVCHD to speed up rendering time and minimize encoding errors. However, if the tracks are filled with graphics/titles, voice-overs, narration, transitions and inserts, then there's no speed benefit for rendering AVCHD-to-AVCHD. (There still might be an encoding quality benefit, however... I'm hazy about that.)
On the other hand, I load lots of video to YouTube, and long AVCHD files take f-o-r-e-v-e-r for YouTube to process for viewing. So I usually render videos destined for YouTube as MP4, which YouTube processes quickly.
If I know the video is going to be primarily played on PCs (as opposed to Apple Mac computers), I render to WMV files. PCs seem to have the least trouble handling HD WMV files, but Macs can't show WMV files at all.
Of course, if it is for a standard DVD, I render as MPEG2 standard-definition (720 x 480) files.
So in my experience, the answer to your question is: It depends.