Here's my experience after a few days of riding with the IICE Air:
Bike: 1997 R1100GS, "Euro" model (no cat, no O2 sensor), ~220K Km
Setup: all original, no mods, IICE Air at -20 default setting
Result: I simply love it!
Overall, the change is very subtle - my iron beast didn't transform into a racing cat...but after 4 years of ownership, I feel it finally gained my trust.
I'm a "torque" guy, so I particularly feel the change in low RPM, when I'm pulling out from ~1000RPM in 2nd or 3rd (now even 4th) gear.
No more of those annoying "hiccups", the throttle is great, acceleration has a "wet" feeling now, and the engine just pulls happily forward.
As a side bonus, adding the IICE Air also eliminated all backfire issues that occurred randomly every now and then.
Oh yeh, and I have no idea why, but my ABS used to fail on almost every start due to a weak battery...issue solved
to summarize - exactly what I needed! great job! now lets talk about that Cool thingy...