I'm fairly sure that, after a certain version in the 8.x branch, sendmail comes with open relaying disabled by default. Unless you turn it on deliberately, you should be safe from that security problem at least.

Sendmail isn't as difficult to configure as people make out, especially if you're only doing minor stuff. Obviously if you want to host dozens of virtual hosts and have some complex forwarding/mail delivery set up then it might get more complicated, but the computer society at my university manages to use it without problems to handle mail for hundreds of users and dozens of virtual hosts.