There are many different gauges out there.  In both brands and types.  So I thought if you could see pictures of all the different brands it would make it easier to decide.  I'm displaying mostly boost and exhaust tempature gauges.  3/S owners may also install fuel, oil, and A/F gauges and who knows what else.  The boost and exhaust gauges are the most popular.  And most people would agree that if you are going to purchase a boost controller of any kind, first you should install a boost gauge.

A great place to buy Autometer gauges is CarParts.com.

Autometer - 2 inch, boost and fuel gauges

VDO boost gauge

Apex-i boost gauges

VDO exhaust temp gauge

GReddy boost gauge

Apex-i exhaust temp gauges

GReddy exhaust temp gauge

SPI boost gauge (I think Stillen sells these under there name too)

Blitz boost gauge

HKS boost gauges

Single gauge pod

Double gauge pod