I like how it makes scheduling so easy! The interface isn't too flashy but there are plenty of options available (which you can customize) as well as filters which make finding what needs done very simple.
There aren’t many downsides - some features could be more intuitive/intuitively labeled such as "posting status updates" vs "sharing posts". However this has been fixed in newer releases since we've started using them at work. We use cosend primarily because our clients want us manage all aspects related with posting content online rather than just writing blog articles or doing SEO tasks etc., they also need help managing multiple accounts across different platforms i.e Facebook & Twitter along with Instagram account setup / maintenance.