I setup iRedMail on a cheap VPS and it works great. I'm not sure about your import process but at least for the mail server it is flawless, and because it uses MySQL as the backend it is super customizable.
I setup iRedMail on a cheap VPS and it works great. I'm not sure about your import process but at least for the mail server it is flawless, and because it uses MySQL as the backend it is super customizable.