[Marco van Herwaarden]

I doubt merging the databases would make any difference (maybe even negative). Change DB is a very inexpensive operation and will anyways need to be done once for each connection. I don't know how your custom application is written, but it will create a connection to a database anyways, this connection must select a database to operate on and i doubt your application will re-use the vB connection even if they are both in the same database.