[stomachmonkey]

Pretty much all of those utilities are front end gui's for the underlying libraries/codecs that either come with or are added to the system.

How well they work depends on how well they hook in.

DVD's are already compressed and there are multiple options for the audio codec which can create issues when you come back the other way.

I am a fan of a utility called Mpeg Streamclip from squared 5. Freeware, works really well.

I would recommend experimenting with different audio codecs until you are happy. May want to consider H264 which is a subset of MPEG 4 but allows lower bit rates for video while maintaining quality. May give you the headroom to bring the audio bit rate up.