I found with this mod, it works very well when you start the car from cold. As you drive around and the engine warms up, the inlet manifold stays cool.
However, if you park for an hour or so, the entire engine bay heats up, including the inlet manifold, and this gasket can offer no protection to increased AIT's. Once the inlet manifold is warm, it takes a looooong time for it to cool down. However, on boost the AITs drop as the air is cooling the sensor. Just what I've noticed after running this gasket for a while now.
I'm going to weld a bung into my intercooler piping and run a new AIT sensor that hopefully wont suffer from heat soak.