First and very important advantage is the Security - VPS has low risk of unauthorized access from hackers or other customers, because each VPS is indeed isolated virtual machine from all other VPS machines. This makes VPS Hosting highly secured compared to shared hosting.
You are the person to administer your VPS and that's why you are in control of your VPS. You can install any applications or modules you need for your web site and web based systems to run on your own VPS.
Performance Reliability is the second and one of the most important advantages the VPS Hosting has. One single customer cannot exhaust large share of the resources but actually exhaust up to its allocated resources. This assures reliable and predictable service for you.
Dedicated Mail Server
Each VPS has its own mail server with its own dedicated IP address. This prevents your email capabilities from being blacklisted.