It really depends on what your needs are and who your providers are. However the difference between vps and dedicated is that with dedicated you are the only person with files on the server while VPS is a virtualization environment where everyone gets root access inside a virtual machine, but there are multiple people with these VMs on one given physical server.
If you are comfortable managing your sites in a VPS as root, then it won't be any more difficult to manage them on a dedicated server.