I think its best to work with people who are more knowledgeable in their area, than with people you are close to. I think its a bad idea to work with people you are close to just in case something goes wrong within the project, that will cause disagreements, and potentially ruin the relationship. However, as long as your team is willing to communicate effectively and handle these issues accordingly, then it shouldn’t be a problem. Working with people that are knowledgeable in their role allows for a better dynamic of the project team, because they’d know how to handle and fix any issues regarding their tasks. If I had to form a project team, I’d first figure out the type of expertise I need (quality engineer, mechanical engineer, biomedical, etc), and then find people who are experienced in those areas.