Project.co is easy to use and very flexible. It is the closest thing I have found to Basecamp, but is a much better value. Unlimited clients and guest allow this platform to be very scalable. I do wish that all of their plans offered a bump in storage, but the ability to easily embed is a good workaround.

This platform is easy to learn and use right away. I also appreciate the energy and enthusiasm of the founder and his support team. They are clearly committed to ongoing development and building the platform for the long term. Another plus is that they have client software, and native mobile apps that all work great.