For non-technical users, you must use Plesk. Want to use WHM because cpanel is more familiar? Won't support the server at all.
Want to use CloudLinux because it makes multiple PHP versions easier for the less technical? Won't support your server at all.
So it's only fanatical support for a subset of what most vendors usually support.
Don't get me wrong, support is better than what you get with say eUKhost but a lot of stuff is faster to just do myself than pick up the phone and listen to some bad techno until I get through to Linux support.
Fanatical Support my arse.