the light flywheel makes the car rev quicker because there is less mass to push. This means your in VTEC country earlier which is a good thing.

Also because there is less mass to push you will regain hp that was being lost to pushing the extra weight. So on the dyno you will see more hp at the wheels, but your motor will still be rated at 145 hp stock.

The light flywheel will reduce driveline losses. For example an EX F22 puts about 115 hp at the wheels on a dyno if you assume a 20% loss through the drivetrain. Change the flywheel and now the loss is maybe 10-15% which translates to close to 120-125 hp at the wheels. The motor is not producing more power, only more of it is being put to the ground.

The downside of light fly's is that you lose revs quickly when you are coasting (no gas applied), but this may be good if you need to slow down quick. You should save money on gas if you drive gently, but becuase you may need to put your foot on the gas when you normally would have coasted you will possibly burn more fuel.
They are also supposed to be a bit noisier than stock.

I still think its a win win situation.

Personally, if I could do things over. I would get a lude tranny for the tighter gearing and a lighter flywheel first before I/H/E. This would give the most gains in the 0-60 and quarter mile than i/h/e on an F22. just a thought.