As far as ripping goes, there is no loss of quality. And if the tartget media is of sufficient capacity to to burn the ripped DVD, there is no quality loss, except maybe due to the media or bad burn, but not due to the data.
Now, issues start when you cannot fit the ripped source onto the target media, as when 8GB movie and 4.4GB target media, mostly because Double Layer media cost over $8 each, and quality SL cost 35 cents and less.
To keep original quality you can split the movie onto 2 separate discs.
The stage where you lose quality is when you transcode the bigger size into smaller size. If you ask me, I cannot really tell the diference at 70% compression. You may increase quality if you get rid of unwanted parts of the source DVD, such as extras/previews/audio/subpictures.
Make sure to read the many guides on the subject of how to put DVD9 onto DVD5.