Here's what I would say:
The way I select systems and servers is first, do a requirements analysis for the server, or for the types of desktop/laptop systems. I have found that in most companies there are perhaps three or four different types of desktop/laptop configurations needed to satisfy user requirements, and I would analyze the user needs (types of applications).
Then I would get up-to-date information from the first-tier vendors (Dell/Gateway/Compaq/HP) to evaluate not only system performance and available options but also warranty and lease options. I would then decide on the handful of standard configurations we should use. The advantage of vendors like Dell, Compaq, and HP is that they will offer the same configuration for a period of time, allowing us to be able to stay with a few different configurations to reduce support costs.
For servers, a more thorough needs analysis would be done including forecasting storage requirements, processing power, maintenance costs, and upgradability.
I would consult independent reviews to learn of any unusual experiences the reviewer may have had, but no review can address the specific needs our firm would need to satisfy.