I am going to go with Autometer for my gauges, here is why:
1) Affordable: When you compare prices of Autometer to the other brands available (Greddy, Blitz, etc), the Autometer gauges are way more affordable.
2) Reliability: Autometer meter gauges are found is most "American" style race cars. Look inside a NASCAR car or any SCCA racer and you will most likely find an array of Autometer gauges. Why? Because they work; they are consistent, reliable, and accurate.
3) Style: Autometer has come out with some pretty stylish gauges. I find the Phantom and Cobalt series pretty hip, although I am going with the professional series for my gauges.
4) Numbering System: We live in America, although we drive Japanese cars. I know converting from Bar or Celsius become second nature over time, but I like to read gauges that use a system I am used to: PSI and Fahrenheit.