The cynical amoungst us would agree. Personally I think that you get what you pay for.
Unfortunately with Time there seems to be a lot of corners cut to get the price down. The badly built, and poorly spec'd machines I have seen from Time would lead me to never buy from them. Coupled with the problems friends and colleagues have had with them. Its worth doing some research on forums and magazines for reviews and opinions on products, but don't forget to ask friends and family what there experiences are of products.
At the end of the day you have to make choices and sometimes comprises (unless you have a hefty wallet) when buying a pc. To be fair most companies provide OEM versions of software to keep the price down. It varies whether full XP cds are supplied (Time are not alone in not supplying full disks) Attention should be paid to what components are supplied as a common trick is to have a vaguely worded description of things like graphics cards which may lead the unware into thinking they are better than they are. Also all warranties are not created equal. Check carefully the terms and conditions, also whether it is onsite. Some companies like Mesh have a active forum presence in the event of problems which seems to have resolved problems quickly for disgruntled forumites.