The way their service works is you choose the number of nodes you want and are billed accordingly. You can choose to add (or remove) additional nodes at any time making it easy to scale up your virtual hardware at any time.
Each node has 0.4Ghz of dedicated CPU, 256MB of RAM, 10GB of storage and 250GB of bandwidth. If you buy one node it's $20 per month; two nodes are $38 per month; three nodes are $54 and so on; i.e. it gets cheaper per node as you buy more.
After buying some nodes you then create a new VPS and can choose whether to have it hosted in the USA or Europe.
They've also just added a way to add additional disk space only at $10 per 25GB per month.
Brief Review
As at the time of this post I've been a VPS.net customer for 36 days. You go along to the VPS.net website, move the slider to the number of nodes you want, enter some details including payment details (credit card direct with them or using PayPal) and within a few minutes you have a working VPS ready to go. Perfect. Quick. Easy.
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