PostFix-Dovecot : Question on installing iredmail or zimbra Found Solution in virtualmin itself THANKS virtualmin

Has anyone installed iredmail or zimbra on their linux server? Does it cause any conflicts with current installs of postfix dovecot?
I understand very little of the two packages that are open source yet they also offer a high priced solution for certain aspects.
I understand that iredmail is a packaging of postfix dovecot and a few other packages offering a solution. Are you using any of these ei iredmail or zimbra??
I have had a qmail install on other older machines and qmail+vopmail unfortunately DOES NOT work with new versions of virtualmin as it does not show user mails feature. So that discourages me to not use qmail.

PS: I found solution in package of postfix + dovecot - most difficult to configure and can be most confusing for someone who never used these.
Once postfix works, I was going to install postfix admin but I chose instead creating mail accounts under virtualmin and it resulted in much better idea.
Postfix admin may be good for very large no of users + using mysql. virtualmin is good for perhaps less than 50 or 100 users OR may be for more.

My question is is there any way in VIRTUALMIN to create users with mysql if eg. we have more than 50 users?

EMAIL SPAM N VIRUS DELIVERY? Configure the delivery methods for spam and viruses detected in email sent to this virtual server.?? Is there any way to add a PREFIX on mail with SPAM POSSIBLE if delivered to the user?

EMAIL SETTINGS > Cloud mail filtering provider ?? Do these filterting services need to be just selected here or installed too?
Is there more detail on this feature?

Mail Client Configuration ? This feature on virtualmin looks very good. I hope it works as it says.