The best thing about Pivotal is that everything is on one page. I remember hour-long triage sessions with Jira, moving bug fix targets between releases. Page reloads are a timesuck. On Pivotal, there's one page with three colums:
- Current has everything you're likely to get done in the current iteration, based on the team's velocity.
- Backlog is the "nice to have, but probably next week" column.
- Icebox is where we queue up bugs for upcoming releases.
The problem with bug trackers, of course, is that switching costs are huge, so I won't recommend that you switch right now. But keep this one in mind for your next project.