PHP mail() vs component-based mail sending libraries

Question

For years I relied on PHP's own mail() function to send an email.
I have just started to experiment with swiftmailer and PHP Mailer which allow you to send mail via SMTP.

Does using such a library to send email via SMTP increase your chances of delivering mail successfully compared to PHP's own mail() function?

Answer 1

Those alternatives make life easier, especialy in cases where you want to send UTF-8 content, since that is a very tedious job. First of all the RFC's are not easy reading and the documentation of the php mail() function is incomplete, and there are even some mistakes in it.