Mailchimp is something that alot of people love to hate. It's a fair argument, the product is expensive, the UI is messy, and it has tons of competition. The reason I still use it is that no other email marketing platform has the integrations and features of Mailchimp. The chimp reaches everywhere on the internet, you can't escape it. It has solid features and if you take time to configure it correctly, it will do 99% of what you want.