We had about 20,000+ contacts in Mailchimp but we rarely emailed them -- not even once every month. Overtime Mailchimp became less of an email platform and more of a contact storage thingy. If i remember correctly, we were paying around $150 every month. While we knew this was high, we continued paying since we were busy with our main product. Money-wise, $150 every month was not a concern for us.
We were also using Intercom. I believe we were one amongst their very early users. Intercom used to cost a flat $50 per month. It was a simple and beautiful product. But over the years it had gotten prohibitively expensive. They changed their pricing so many times and complicated their product so much that we gave up. You now need an advanced degree in math to understand their pricing. Truth be told, Intercom still does a couple of things very well. Don't let our experience prevent you from trying it.
Mandrill was the product we used for transactional email. Sometime in 2016 Mailchimp decided to end the free plan. The only way to continue using Mandrill was to make it a paid add-on to Mailchimp. This act by Mailchimp triggered some amount of road-rage with a few team members (see, we were already frustrated with Intercom). They saw this as an act of ransom. A few days and a few meetings later it was decided we roll our own email sending smokes.
We decided to use AWS SES. The little software we wrote to integrate with AWS SES was quick and dirty. But it did what it was supposed to do. In under two months we had fully exited Mailchimp, Mandrill, and Intercom. We went from paying $200+ a month to ZERO.
Over the last two years Send With SES (which is how we internally referred to our little email sending software) received contributions from whoever had time to spare. It became robust and moved from an in-house server to its new home in AWS. During this period our AWS bill for Send With SES used to be around $125/month. Currently (early 2019) our email list is 75,000+. We still rarely email our users. Had we been on those other platforms we would have easily been paying over $1,000/month.
Sometime during mid-2018 it was decided to spin out our email sending program into a SaaS product. Initially we decided to call it abcd.email (the product is as simple as abcd, you see). But we settled on sendwithses.com - our internal name.
Send With SES was scheduled to launch early-2019. After skipping multiple deadlines Send With SES (beta) was launched on 15-April-2019. The damn newsletter composer took a lot of time to perfect. It's the easiest to use newsletter designer now. You should check it out.
Send With SES will always be easy to use and cost a lot lesser than Mailchimp, Intercom, or any other email software. We have a Total Cost Estimator.