I'm not sure about what kind of technical support you are referring to. If you're talking about general computer help, I wouldn't call any of them because they may or may not be able to help you depending on the issue. They may also outsource their first level tech support to other companies. If you're referring to customer service for warranty issues on the hardware, make sure you understand the warranty on whatever computer you purchase. Most consumer grade computers will have a 1 year warranty, but it may require that you ship the computer to them for repair. You may have to buy extra warranty coverage to get onsite repair. As for who has the best onsite repair, I've only really dealt with Dell and Lenovo, both of them seem to be good about responding quickly. I have not dealt with HP onsite support.
Behind every good computer... is a jumble of wires 'n stuff.