Plesk is by far the better panel. If you are installing it yourself, it installs in about 15 minutes. It has a choice between power user and hosting user admin panels and as mentioned by other member, it is all in one interface, not like having WHM and cPanel separately. Plesk is also the ready-to-code platform providing an amazing tool, the Wordpress toolkit for those of us in the WordPress community. If you work with WordPress, then Plesk is your only choice. Plesk is also perfecting Python, RoR, Node, Django Support. Plesk Onyx testing is working with Docker, will have Multi Server management, and also includes the best security out of all the panels. Want access to use your own Git repo in Plesk or connected from Plesk to a Git Repo, Get Plesk.
cPanel is well know and has been around, but it seems to only want to be a control panel with a one size fits all mentality. While they do have a large chunk of the market, they are not the global leader. Look to Plesk as they hold that title. Install time can take well over an hour to install. The panel is not easy to learn and the menu on the left hand side goes on and on for days.
Direct Admin is good for low priced panels. The install is based on a script to install as well as reconfigure. It pulls down source packages and it compiles everything custom for your server, which is very cool, but again takes time and if there are package or patch issues, you need to wait for them to redo the script to integrate patches to the source. Direct Admin also has challenges as the UI is the same as it has been for about 10+ years and it is not easier to day than in the beginning.
I have been in hosting and have run my own hosting and design companies since 1995. I have used all three solutions, and currently have both Plesk and cPanel systems. Plesk had some bad times due to focus in the past, no doubt... but now Plesk is only Plesk... if you have not checked Plesk out... Then you are missing the boat.