Wow, had to ask, born cynic and all.
I have read more than once that these things are just hype (getit). Going up 30 points on the jetting is HUGE. My gsx went up by those levels when TTS upped the horsepower, in the end by 40% from 62 to 104hp RWHP (dyno'd) consuming quite a lot of money at the time too.
You are really going to feel that at the pumps. My gsx went from doing 180-200 miles per tank new, when she was fully worked on you could, if you really caned it get 65, yes 65 miles to a tank. That's 4 gallons, gone! 600cc doing 16mpg. Actually got it down to just over 50miles on mad Sunday at the 2000TT. Riding gently i could get 120 ish. Or 30mpg, hardly economical.
Properly planned and executed tuning is a beautiful thing. Its worth every penny, to feel the bike as is was designed to be rather than the average everyman version it started as. Its now YOUR bike more than ever.