I noticed that the last update of RB Pro came with a new encoder option "Cmdline encoder." What exactly is this and how does it stack up against some of the other encoders?
snippet from here - http://www.jdobbs.com/Pages/DVDRebuilder/History.htm September 4th, 2007 (v1.26.3) CHANGES MADE TO VERSION ONLY * Fixed an error in which the REDIST_ALL parameter was not being set correctly when selected. In the previous version any change to the setting was not recognized until the next program load. * Added Beta support for command line oriented encodes (e.g. Mencoder or FFMPEG). DVD-RB will call a preconfigured .BAT file that can be setup for the calls. An example .BAT file (for mencoder) is included as an example. In order to use it, you must edit it (it is normally found in the "c:\Program Files\DVD-RB Pro\Encoders" directory) and point ensure the path properly points to MENCODER.EXE. You must also add the line "cmdline=" to the "[Paths]" area of the REBUILDER.INI file. This new option should be considered in Beta test until it has been used more. My encodes (using M encoder) so far tend to be undersize -- but very good quality. Try the "Good (fast)" mode, it gives very good quality and is exceptionally fast. Be careful with "Highest Quality" mode -- it can be slow.