I am currently using a shared hosting but due to increasing traffic and server load my existing host is not able to provide reliable services and I am planning to upgrade my hosting service.

While I was searching for Dedicated Servers, I learnt about Virtual Dedicated Servers but I am not very sure about their reliability? Are Virtual Dedicated Servers useful? My website current serves over 2500-3000 visitors a day resulting in 30,000 pageviews and I am expecting the traffic to grow by atleast 2 folds in the next few months as I start some PPC campaigns and Email Marketing for my website. Can a Virtual Dedicated Server cater such needs assuming my website to be more of less dynamic website written in php?