These example suggest there must have been a list of units and names that transcended the medal rolls we see and that guided those naming the medals to deviate from the rolls. An earlier post in this thread provides one example of this information.
Most definitely David. The rolls we look at were a working copy kept in the "medal office" and annotated through to WWII judging by the remarks added in. There must have been a separate copy sent to the Mint for making medals up.
Kevin Asplin's QSA cavalry roll only covers the medal rolls named to cavalry regiments. It does not cover the Remount rolls - which are a pain to work through - but in here lie very many QSAs named to cavalry regiments; as Mike has shown in his post above.
I think that even if I were a regimental collector, to be quite honest, I rather doubt if I'd go the extra mile to buy one, if the majority were simply reservists who had at one time served as wretched cherry pickers.