NT and NTBackup

The company I work for does not want to part with money. So they have been using NT Backup as their backup sloution. Recently the company moved from having one server to three. NT Backup was always set using the command scheduler to run automatic. With the addition of the other two servers it is still only backing up the server the tape drive is on. Plus the amount of data being backed up takes 24 hours. How do you convince them to change? So far I have been told I need to call a self-proclaimed expert that they know. They don’t want to take my word for anything that this is not the best solution, instead they want proof that I can give them. Any ideas?