By the way,

The Blitz DTT has the ability to display a Boost Reading and also an overboost warning (which beeps and changes the display colour if you hit the boost level set by yourself). It doesn't allow Boost control though. It also has an Automatic function that decides how long it wants to run for, depending on how the car was driven.

The Greddy unit also has the ability to calculate the amount of time required to cool the turbo, but doesn't have the boost display.

Not sure how they integrate with each alarm brand though.

Will try and find out.