I like the fact that it's frictionless, minimal and fast, with a generous free plan and excellent paid features at a fair price.
Easy to use; easy to work with others; responsive and friendly support; no training required; and the interface is nice and clean.
But a supervisor of mine invited me to use Quire to coordinate our summer camp together and my goodness it's so great. So intuitive and easy to access.
Difficult to say... i have to sing-in for all Members to do the configuration (no Admin-Tool or default settings for whole organization).
No way to stop an E-Mail from being sent to everyone in an organisation when creating a project in an organisation.
At this time I have not ran upon anything I dislike about this project tool.