it is true i do have one :P

As ben said i dynoed my car after there was no improvment in KW numbers
although the curve had more of an angle to it steeper climb :P
when i first drove the car from the garage i was very happy felt like a new car very responsive

when you let your foot off now you will notice a bump especiely in 1st gear because the flywheel does not have as much enertia being lighter so it stop/slows alot quicker this is something you have to get used to
its not a big deal :P

good luck with purchase you should be happy if you stick with the brands mentioned

there is another option where you machine the stock flywheel taking off excess metal this lightens the stock wheel but can casue problems in the long run the wheels becomes weaker and prone to warp and or cracks, the right person has to do it for you