A good comparison of using a virtual private server is the process of owning a condo. You share the property with a few others but have ownership of your own space. Medium sized or growing companies who desire a bandwidth upgrade are perfect VPS users. For a moderate cost increase, they have a more customizable, reliable and secure system than they would have with shared hosting.
The answer is simple – despite having many different names, all of these companies belong to the same German AttractSoft group. That may not necessarily mean something evil – it could be that each service is just meant to cater to a different market and/or audience. For example, Awardspace is more popular in the US and India, while Netfirms is a well-known name in Canada.
Many services offer a low "starting price," but require you to prepay for two or three years of service to get that price. After the promotional period, the renewal price for some services can be two, three, or even four times the initial promotional pricing. While the initial deal might be incredible, the cost of transferring your site (or paying the added fee) in a couple of years may be something to consider.