Evaluating EPM Partner Solutions and Applications built on Project Server/Portfolio Server

Joel Oleson blogged today about: Evaluating SharePoint Partner Solutions and Applications built on SharePoint, he summarized five questions you should ask when evaluating a custom solution:

  1. Do they directly update or modify the database?
  2. What is the residue or footprint if you remove it?  Is it a solution or feature? Can that solution be removed cleanly?
  3. Do they have an upgrade path?  How will this be upgraded when it's ready to be upgraded?
  4. What is the support and sustainability for the app or solution?
  5. Does it scale?  How does it scale?

I strongly believe the same questions can be asked about any solution/application built on top of Project Server or Portfolio Server.