I tried the free tier

I tried the free tier. Bad in 3 ways :
1) Documentation less clear than GetResponse, Sendinblue, Mailpoet
2) Mails don't go through hotmail, live, outlook, msn
3) Last but not least, they block you without warning and without reason (they tell "it's the system") and so blocking your business with no reason.

My worst experience with an email marketing platform.