We are currently using Visual Studio 8 with Visual Source Safe. Due to customer requirement, we must migrate to either PVCS or Rational ClearCase, Team System is not an option. Please recommend one of these two options, giving pros/cons from experience with each. How well does each integrate with Visual Studio 8?
There is not enough information to recommend one or the other. I've administrated both systems for more than 10 years. Currently I'm a ClearCase administrator.
Questions to answer: how many developers are there? Are they spread across multiple sites? Is it 100% Windows or is Unix also an environmental possibility? How much data is there to store?
ClearCase is industrial strength, but it is also ridiculously expensive in every way possible - from licensing to equipment and human resources necessary. It scales well but requires a strong server environment. It is extremely complicated to administer, especially in mixed O/S environment. HUGE learning curve for new users, HUGER for new admins. It can be perversely slow and the server has beefy hardware requirements if you want reasonable performance. ClearCase supports multisite environments in multiple ways. It's very capable as payback for all this expense and complexity. Be ready to hire at least one full-time administrator. I'm serious.
PVCS is a solid, reliable system that does not always require a server. It also scales well (I once administrated a PVCS project with 140 developers). It is easy to administer and easy to learn. It does not have anywhere near the feature richness of ClearCase. Many would say that's a good thing. It's much simpler and less prone to trouble.
PVCS is much more like using CVS than ClearCase is, if you want to compare other tools. ClearCase isn't like any other source control tool.