I have this case where if the data pertains to a certain product we want to store in a different storage provider than our default one. As far as i could see you cannot really script conditions on the storage provider. Any thoughts on how i could do this?
Don't use the historian at all. Use tag change events and/or timer events to script the insert of history to your database, selecting the right one on the fly.
Store in a single database first, and then synchronize data based on conditions. If the data on both sides is inconsistent, it will be too troublesome.