I am a small business owner. I have used different email marketing tools, including mailchimp. I am using convertkit now. I pay a lot of money but only use limited features. I saw Inbox and bought it. I transferred my subscribers to Inbox and Inbox instantly segregated my list to , valid, blocked and invalid. I never knew I was paying for "subscribers" that are not valid and cannot go through.

The event concept appeals to me. I am currently testing it and I can see the potential for this feature.
Thanks, Inbox team, great job. Looking forward to more features!