Although the RCE might be gone within the vob files , there still can be some initial software residing in the first vob , which checks if your player is region 0.
I've never tested DVDDecrypter and i only have one RCE disc (X-Men 1.5 DTS Region 1) , but i know for sure SmartRipper doesn't do the job. Perhaps DVDDecrypter/IfoEdit are lying as well ?
The latest
DVDShrink beta says it removes RCE as well , perhaps worth the try.