we use Plastic SCM allready for over two years. it's probably the best product for doing SCM. Having used PVCS, Subversion and ClearCase in the past. I definitely recommend using the branch per task approach used in Plastic. It makes your integration work so easy.
Using scrum or another extreem programming process, plastic enables you to control the code in a very easy way.
Plastic is also evolving very fast and has a very strong technical team behind its development.
