Recently, I wrote a GigaPulse tutorial for Tascam. It's now up on their site!
The idea is that we want to create a complete soundstage, and we want to do it efficiently. You can't just throw a new impulse location at every instrument in the orchestra, unless you have a rack full of PCs.
The tutorial shows how to setup your GigaPulse instances and do all of the routing in GS3's DSP Mixer to get the most bang for the buck. With three impulse locations, you can place every instrument in your orchestra. I even included an audio demo.
Let me know if you find the tutorial to be helpful.