Thanks for the suggestions, but I may be switching to Premiere despite the much higher cost. I downloaded it and played with it for a couple hours this evening. It seems to handle the big files without a hiccup, no caching time. And there's an automated multi-camera sequence function that will automatically sync two or more clips according to the audio track waveforms. Then one can just play the sequence and press control 1, 2, 3, etc. to switch between the video tracks wherever one wants. No splitting, transparency effect, deleting bits of the tracks, or any of that. If I can climb the learni