When a company has won several independent awards for their PCs they are more likely to know what they are doing when they are building yours. Some firms go further. Always make sure you understand whether the warranty is on-site, at your premises, or RTB, which is Return to Base. Do remember that your warranty becomes virtually worthless if the company that provides it goes bust. If the company you intend buying from has been around a few years there may be a better chance that they'll still be around when you need them in the future.
Most new businesses fail within the first few months.
Companies that have been accepted for supply of computers to government departments, local councils, hospitals, educational authorities etc may have passed several quality tests to ensure that their computers meet with the respective department's own internal quality standards. The cost of registering a domain name is now under the 100 mark and the software needed to create a web page is virtually free. Call their technical support line to see how long it takes to get through. Do it at several different times of the day. Good luck with your purchase.