I have a 10lb Fidanza for both my cars. I like the way the engine behaves with them. However, if you're going to get a light flywheel, I would get one with a replaceable surface area. That way if you're using an harsh clutch that wears it down quickly, you don't lose your money if can't be turned. I have no complaints with AZZ, Dave is a good guy, but his lightened flywheel is just as expensive as a Fidanza, and it doesn't have a replaceable surface.
PS - Tim Ogburn (TimO) is a Fidanza dealer. Do a search on his username for contact info.