Sorry I should have been clearer, it was both the practical and perceived results I was referring to.
You can compare different transcoders on an equal footing or different encoders on an equal footing and the difference is subjective but the difference between transcoders and encoders is so apparent it's like chalk and cheese.
My preference for the DVD Shrink output over the DVD Rebuilder output is entirely based on re/trans-coding of very long movies (3 hours and more) to fit on DVD Single Layer media and based on viewing the video as it plays, not looking at still images of the video.
This is exactly the scenario when the differences between transcoding and encoding are most pronounced. Transcoding is NEVER anywhere near as good as a full re-encode in those circumstances.
Let's stay focused on the original poster's questions in this thread and not on my setup of DVD Rebuilder.
No worries, just trying to assist.
My point is that not everyone will prefer the output from DVD Rebuilder compared to the output from DVD Shrink, and that it might be worth experimenting with the options in DVD Shrink, since that's what the original poster is already using.
For high compression levels that just doesn't make sense.
I'm not trying to attack you in any sense but I just feel it's a bit misleading to others to imply that any form of transcoding could be superior to a full re-encode both from a technical perspective and from the real world perception of the results.
If the compression is extremely slight (a reduction of 1-2%) then there's possibly some small scope for debate and some people argue that CCE can introduce extraneous/unnecessary noise at those extremely low compression levels, but for high compression levels the difference is so pronounced that I'd have thought it was impossible not to notice the difference even on a small TV.
Personally I'd advise the OP to try the trial version of DVD Rebuilder on the film they're having difficulty with and see what they think, then they can let us know their own results.
Quality wise, out of hundreds of re-encodes, I've only ever found a couple of dual layer originals that were already so highly optimised that in my mind even a full re-encode wouldn't produce acceptable results.
The results of transcoding of those discs would be genuinely unwatchable IMO but that's another story.
I'm very particular about quality though and, whilst I realise that others may be satisfied by less, in my experience a full re-encode can never be unequivocally beaten which is about as good as it gets in my books.