I need to send a large volume of emails, roughly 60.000 per week. At the moment we outsource this service to a third party, and we expect to double our volume within the next 6 months. Since the service is starting to be too expensive, I was thinking about setting up our own MTA.

Our own SysAdmin told us it is not difficult at all to have our own MTA, but I'm afraid he might have oversimplified this.

Is it difficult to handle a MTA? Should I be afraid that my MTA will lose the company mails? Should I stay with a third party service?

p.s: The emails have been collected respecting the local legislation on privacy, so no spam.