You are comparing two software programs that compress/transcode the DVD video in two entirely different manners. The fact that the same size DVD files were compress/transcode at different percentages but ended up the same size when finished proves that fact. Your comparison percentage numbers that you referance is like comparing apples to oranges.
You be the judge and tell us which one looks better. You have the two different backup copies that you made with DVD Shrink and CloneDVD. Pop them in your DVD player, you view them, and then you tell us which one looks better.
Suggest you view a recent CloneDVD Forum posting that asks the same question you now are asking (CloneDVD compression quality vs. Shrink/Recode?)
Maybe this fact doesnâ€™t mean anything to you but DVD Shrink is a â€œDeadâ€ software program that isnâ€™t supported anymore and hasnâ€™t been updated in a year whereas CloneDVD is fully supported and routinely updated and improved.