I have been using AccuRev SCM for about 4 years and every year my impression of this system gets worse and worse.
The AccuRev bills itself as a better replacement for ClearCase. I can surely tell you that it is not better and there is no love lost between me and ClearCase. I hate ClearCase with passion for its slowness and complexity. ClearCase however has two big advantages over AccuRev - it is reliable and it is documented well.
AccuRev is simple as long as you only have to check-in files and make them visible to everyone else. As soon as your workflow deviates from the one above, AccuRev becomes a time sink with countless hours wasted. You know what I am talking about if you ever used AccuRev. Try for example rolling back to any previous checked-in and promoted version. Simple solution would be to get the old version and check it in on top of the latest one. That does not work in accurev - file becomes "underlapped". Revert command is disabled for unknown reason. Every time I have to do this I run in to a new problem of some sort.
The documentation is terrible, covering only the basic use. The UI is terrible with menus greyed out and disabled in seemingly random fashion. Command line is somewhat usable but occasionally commands fail with cryptic messages and you can not understand why.
The actual source control database can die on you at any moment and you will need contact their support to fix it. This sometimes turns in to days of downtime. Their replication model is a joke and the replication itself can stop working without any warning or error.
I also help to administer AccuRev and intimately familiar with all of its problems. I would strongly discourage anyone from even considering using it, especially when such wonderful and reliable OSS SCMs are available for FREE.
Very few people will probably read this post but if you do, avoid AccuRev like a plague