unless you fire an infrared scanner on it in relatively the sam conditions before and after you really will not be able to tell. I know that it reduces the intake heat from migrating up through the super charger though. Its worth maybe 5 ponies but if you hit the trach it will help with keeping things cooler and creating more consistancy. Its cheap and worthwhile. I'm doing mine when I get my ported blower back next month.
I have one on my truck and don't see a reason to take it off - but I also haven't seen proof it does anything beside lowering the plenum temp. While in theory that sounds great, I haven't seen proof that the temp difference is enough to be worth anything at the track.
A lot of assumptions going on with this product. Feel your supercharger between runs at the track - did it burn your hand? Do you really think a slightly cooler plenum matters?
I had meet a guy from Oregon 2 weeks ago on a run for the So. Cal lightning owners. He had one and he said he used a laser thermometer and it read close to 50 degrees cooler than before. He's the only person I know that has done it.
I have one and have installed a few. The EGR tube is just to easy to take off and bend, that spending the extra cash is a waste. Intake is cooler but by the time the supercharger heats it back up and it passes through the intercooler do you think there would be much difference? Also none off us has experienced any better track times with them. Just my experiences.