Plesk is for Windows mainly. I personally prefer cPanel & Direct Admin they are both really good but I would recommend Direct Admin as it is a bit easier to use,
very fast and stable. cPanel loads slowly and may not be as stable as Direct Admin.
If you are doing Windows hosting, I strongly recommend DotNetPanel over Plesk. We started with Plesk and had numerous issues with it, not the least of which was that it was SLOW, SLOW, SLOW.
Even had one customer say that it really "Plesked" her off. (And that's a direct quote.)
We had been looking at DotNetPanel and soon switched to it. We've found that it's fast, reasonably priced, powerful and flexible. We had several customers actually thank us for switching off Plesk and going to DNP.
I think cPanel remains the popular choice. However, IMO Plesk has proven to be much more reliable and secure. cPanel has been plagued with bugs since its conception. However, over the past year or so I believe the have been making more of an effort to pull it together.
My opinion would be Plesk for reliability, and cPanel/WHM for features.