I have the spacer plates and blanket. Will be adding the bwoody race HE and a black market reservoir. These two items will add two gallons to the IC system, which is more than double what it currently is,
I considered the interchiller, too. Install doesn't look that bad, but I just didn't want to mess with the AC system. The bwoody is pretty simple.
Mainly these things will just help keep the temps down over the course of the day running the car. In terms of a single run, when your car is cool, it won't make more power. But over the course of the day, if you are making numerous runs over a couple of hours, then it can help.
If I didn't bracket race, I would have just left the stock HE setup and just used a Tazer. I want to be able to let my car idle for 30 minutes and know what IC temp so I can dial in my time for bracket racing.
Unless you have some specific goal in mind, and if you only hit the track now and then, I'd just use a Tazer and cooldown that way, and throw some spacer plates and the blanket on if you ever do a pulley swap.