Hiya,
While we keep an eye on commercial tools we are not in a position to detail exactly what the differences are - you will need to do your own comparisons.
Note that many commerical DAST tools are actually based on ZAP :D
FYI ZAP is no longer an OWASP project, its is "ZAP by Checkmarx" or just "ZAP".
Cheers,
Simon