I have used Accurev for one year. I don't like it. Here are some problems I encountered:
1. Its GUI is terrible: it's so slow that each time I switch between tabs (streams and workspaces) or perform some actions I have to wait for several seconds. It sometimes gave you a confusing error message that could not help find what's wrong.
2. It has so many concepts that you have to spend much time learning Accurev itself.
3. I once encountered such a problem: I have a version controlled file modified by our build process. Later my teammate moved that file to other location in his workspace and promoted the change. When I run "accurev update" it simply told me "some file has been moved" and everything looked normal. But actually the command stopped at the moved file and no longer updated other files. It's very confusing - your update command did not update the worksapce but you have no idea about it. The only outputed message "some file has been moved" looked just like other verbose output. It did not tell me my update failed or aborted or something else.
Before that I used SVN and ClearCase. SVN is a great tool, simple and easy to use. And I did not have so many complaints about ClearCase. Accurev is really frustrating...