I like this plugin, my only gripe is that MailPoet forces you to send your subscribers a double opt-in to add them to your list if you want to use the MailPoet email server. For this reason, I have chosen to use MailPoet SMTP option so I am not required to send the double opt-in.

I previously bought some Clearout codes on AppSumo and that gives me more than enough power to validate and clean a subscriber list.

My form builder of choice is Formidale Forms, and I was very pleased to find they have an addon for MailPoet which adds subscribers to your MailPoet list.

The email templates are good, and the builder is good as well, no problems there.

For people wanting to create email Campaigns, like in MailChimp, this is where MailPoet is not there yet, there are no triggers other than automated scheduling when a subscriber is added to your list. For me, that's not a deal breaker, and I assume this will become more feature rich over time, hopefully people will get access to new features rolled out on their legacy plans.

I documented some of these experiences in this video review;
https://youtu.be/HhcpHTI3k7o