- Working with large files
- Getting only the needed files form the sever, not all
- Not wasting space with .svn/.git copies of the files
- Reasonably fast.
They have quite some customers in the video game industry because of their support for huge projects and large files. We are using it for a different kind of application with similar requirements (100000s files, size up to GBs range per file). Perforce is well suited for the job and has good 24/7 support.