I don't think MIME::Lite provides access to the messages from the server on successful delivery.

I have used Net::SMTP directly to send simple messages. This gives access to all the replies from the SMTP server but it requires you to deal with all the details. Your example looks simple enough that it might be sufficient.

Otherwise, I have used MIME::Tools to compose and send multi-part messages. If this doesn't give access to success messages (I don't know off-hand), you could use it to compose the message then use Net::SMTP to send it.