sendmail does work but in conjuction with exim, since we have sendmail being used with PHP mail() function. sendmail actually gets automatically reinstalled if you try to remove it on a cPanel machine. We don't support sendmail MTA directly, but we do support using sendmail.
Now, what reason are you wanting another MTA besides the existing exim and sendmail options available with cPanel? If you were considering qmail, please keep in mind that qmail is arcane and old with a high series of patches. The qmail creator no longer provides support for it.
There's a great discussion of the various MTAs at this location:
MTA Comparison - Granizada
In almost every instance, exim is the preferred choice. It is the easiest to configure and setup with a large contributor and user base. It is what we provide and have found after many years to function reliably.