The most important aspect of quality when choosing a laptop is customer service of the company you buy from. Almost all laptops, regardless of brand, are made by the same manufacturers. The major manufacturers do not build or engineer their own hardware, they merely rebrand stock hardware (and often the major brands offer near identical product lines because of it).
For a list of manufacturers and the brands they sell to:
http://en.wikipedia.org/wiki/List_of..._manufacturers