[sualfred]

In my usecase it was a lot faster to get all items all in once and to use the data as long as embuary info is active, but your addon has much more implementaiton scenarios. A caching would still be possible. All that is required is a small service in the background which is listening on VideoLibrary.OnScanFinished / .OnCleanFinished to refresh the cached data. Anyway, if you don't have any performance penalties this is not required at all

But for the skin side of things you always can use the dbid + dbtype to get the uniqueid. But I 100% agree: A direct access to something like ListItem.UniqueID(imdb) would be a much better solution. It could also be used for skins and ID representation in info dialogs etc. Or for calls in other scripts and addons.