If you want new customers for Plesk, a easy transition using some by Parallels provided import tools from common other systems like dns from bind, mail from courier, etc. would be a nice teaser.
#ontopicagain:
Same problem, we are investigating migration to Plesk, but we get no further than using Plesk as a secondairy DNS storing transfered data to bind zone files, but without updating dns records in psa database. Changing it to primairy afterwards is therefor of no use.
#oftopicagain: Searching Google and Plesk forums, I found this question multiple times, back for years...Only useless answers mentioning cli scripts to at least create the domain and find out ourselves, or only repeating about secondary role scenarios (while asking for primairy role) are replied.
PowerDNS has a zonefile import utility for mysqlbackends, maybe we can adapt that script for use with psa, changing some destination column fieldnames. Just a thought.