> Is the kml2kmz just a gzip?
This is just a wrapper around gzip that changes gzip headers to (pk)zip headers and the central directory which is what kmz files are. Most GPS data compresses over 10:1.

>Would be nice to get Google Earth to replay the KMZs in flight sim mode.
It will bounce every 5 minute kml - there is a "lookat". I didn't want to clutter it up too much and it can be post-processed.

I did a 5 minute split to minimize problems when there might be bad data (found a problem with minus signs inside XML comments, occasional system crash, etc.). Also so you can more easily discard dead data or find the point you want.

(losing 1 hour of log is worse than 5 minutes, and searching thousands of lines for a bad marker is much easier than searching millions of lines).