Originally Posted by 4drwhore

Then find what companies sell gauges that read 40psi and then go from there on size and styles you like.

Since you have the aem ems and will be logging everything(I assume) a peak hold gauge is not really needed but wouldn't be bad when you are just doing pulls to check out little things like where your boost controller is set at and what not without having to bust out the lappy and go through logs, just for quick reference type bs.