Agree with all, WHM/cPanel as you will have your own licensed copy under which you can manage the number of features easily, just on one click. It is easy to use and manage.
WHM provides the interface used for administrative control. It is used with cPanel. WHM work as backend. It has various features which are used for managing the functionalities handled using command line access. It comes with reseller service, VPS and dedicated server. Here are the functionalities handled by WHM -
1. Create/delete/update the account
2. Manage the bandwidth, resourcres
3. Handling the DNS Zon
4. Creating the nameservers and assigning them to correct IPs
5. Firewall setup
6. Various Email Functionalities