Brand doesn't matter as much as people want you to think it does.
People generally blame brand for three things.[*]How well the computer runs.
Dell and HP and Apple and other companies don't "build" machines, they "assemble" them. They take core parts (like the processor / ram / graphics card / harddrive) from other companies that make them, put it all together (with their own cases and accessories) and sell the completed package to you. If you ever take a computer apart, you'll notice that the company names on the parts vary widely. There's a few companies that make ram, a few that make processors, a few that make harddrives, and so on and so forth.
So, for example, there's nothing that makes an HP processor better than a Dell processor... because there's no such thing. Dell and HP can both be using the same processors in their machines. So you can buy a Dell that kicks an HP's ass, and then turn around and buy an HP better than that Dell.
A big part of how well a computer runs is the software installed on it (specifically the drivers and programs like that). Most computer issues are software, have nothing to do with the brand itself, and can be permanently fixed with a little bit of effort.
So if you want a faster computer, you should make sure to pick one with the right parts, and maintain it properly.
[*]How well the computer is physically built.
You get what you pay for. If you buy a company's lowest-end model and find that the case is made out of cheap plastic, it's because you paid for cheap plastic. If you buy a higher-end model and get a sturdy metal case, that's because some of the extra price went towards a metal case. You'll pay more for a computer that's built with better parts and more care, because it costs more for the better parts, and it costs more to have workers spend more time on it. Every computer manufacturer makes multiple lines of computers, and generally the "it fell apart" complaints are from people that bought the cheapest one.
So if you want a more sturdy computer, don't buy the cheapest models.
[*]Tech support.
As said above, you get what you pay for. The standard tech support is the foreign people because they are cheap. If you buy the better warranty/support package, then you're paying for the better support people. You have a better chance of getting somebody that knows what they're talking about and who can speak english (or your native language), because they cost more to hire.
So if you want better tech support, you should get the upgraded warranty/support.EDIT: Damn formatting.
Always touching 
] brb