Using same installation for multiple domains

We have several domains and want to use phplist to send our newsletters and marketing campaigns.
What is the best practice?
Shall we install a phplist in each domain or with one installation manage campaigns for all domains ?

Personally, I’d do one installation per domain. If they are all on the same server, you can get away with one database if you have to, just remember to use different prefixes for each.

By using individual installations you can, if you choose to do so, use SMTP to send out thus reducing the likelihood of being classed as spam.

Thanks for your help.