Right now it seems like the ones converted from V4 to V5 with changing SHA1's are worthless so those cases should stay at V4 in your set. At a later date those will be redumped when source becomes available and if possible.
All others that convert from V4 to V5 keeping the same SHA1 are fine to keep V5 in your set.
As far as a list goes I don't have one right now.
****note don't try this without having backups in case I'm wrong about this ******
I guess the easy way to go about it is audit with CMP correctly and set chdman to V5. It will then remove the ones with changing SHA1's which then you can replace the directories that have been removed with the ones from your V4 set (before conversion)