When you are choosing VPS server, checkout the Speed and Uptime. This is important for your audience or users. That which does not want to face any difficulty while open your website. Third Point is check the customer support. How many times they will response your queries? But there are some factors are apply on it that is which type of OS you want Linux OR Windows? Managed or Unmanaged, Bandwidth etc. But I Suggest you to take attention on above three factors that are Uptime,Speed and Customer response time.
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