i personally have 52mm defi's on my 06 and love them. they are very clear and precise. i had prosports prior and they all broke within a year. (they are very hit or miss. some people have no issues w/ them and some people do)

i'm not a huge fan of pillar mounts. i'd go with the SMY

 

Will a dealer give you any trouble with warranty stuff if you add the A-Pillar and aftermarket gauges? I know that they could only deny warranty to related parts so what parts "could" they possibly deny.

 

Depends on the gauge.. I can think of a few scenarios where a dealer would be well within their rights to deny a warranty claim. For instance, say you have an oil pressure gauge, and the fitting for the sending unit breaks, all your oil dumps out, and the engine seizes. If I were Subaru I would deny that claim because it was something you did that lead directly to the failure.

 

I would say get the ATI center pod or SMY pod. A-pillar pods are kinda hard to read and deal with. Or make your own if you're handy with fiber glass.

Defi, Greddy, Maddad make great gauges. Those will be your top dollar gauges with the most features, accuracy, and dependability.

 

I would not go with an ATI center pod. Personally I dont feel there has been a nice aftermarket gauge pod for the center area unless you get some custom work done so that it fits the dash better. For now I have an SMY cluster with prosport oil pressure and boost gauges. I did miss having voltage and other info from my previous car so I ended up getting a UltraGauge it plugs into the OBDII port. Once I have the need for more gauges my choice would be Windshield Dual Gauge Pod 2008+ WRX/STI - Gauge Mounting Solutions
I know that it is not the best solution to constantly monitor since you have to look away from the road but I keeps the inside looking cleaner then the triple pod