haven't used them yet in TH2 yet, but I use IRs in many tracks, because they are naturally sounding "reverbs" that give life to sterile sounds. You can search the internet for wav impulse sounds modeled in various surroundings and use them in the convolution reverb vst of X2. It's kindof like using a reverb... if it doesn't sound right, you're using too much of it. Use a small amount wet, stand back and solo A/B it until you just notice it... it should be a subtle effect that really adds dimension to the sound.