We've been playing with MissiveApp and Front, but not really excited by either as we already finding bugs on both.
Any recommendations?
This is more "ticketing" than "shared email", but about 10 years ago I used Freshdesk and really liked it: https://www.freshworks.com/freshdesk/, once I spent the time to properly set up its rules etc. It was much nicer to work with than Zendesk or Jira ServiceDesk.
Other than that, I've also actually just shared a regular Gmail inbox with several others, and we used a system of labels and inbox filters/sections and such to manage it. That actually worked surprisingly well for our small team (3-5 users).
Hope someone else has better recommendations...