The Export to list shows 2 avi selections. I tried both. The avi selection at the top of the list exported as avi (with the expected huge file size, and lots of glitches in the video). The second one (at the bottom of the list) imported the clip as mp4 (what I usually use), and is the same file size as the mp4. It's the 2nd one I'm curious about. What would be the difference between straight mp4 and the avi which exports as mp4?