How many contexts?

We have been working with Windchill PDMLink (10.1) since 2012. Until now we have been using Windchill only for CAD, but now we want to incorporate everything into Windchill. We are therefore reviewing our routines and trying to adapt the "Windchill mindset". In this case, what is the Windchill philosophy regarding contexts?

• We have many different customers and projects in our organization. Should we create a new product context for each new project? (Our products is often “one of a kind”)
• Until now we have been using only one product context, with a folder structure representing our customers. Is there any downside to keep working this way?

Thanks,

Ørjan