Great topic guys, something that isn't discussed enough...
For the guys who do not belong to a fishing or ski-boat club, having flotation would not be a requirement (no enforcement). Although, personally, I feel it to be a necessity, especially this side of the world.
Prior to registering at the local ski-boat club my Bamba needed a buoyancy certificate and even when produced the craft was still inspected. The guys from Fluid simply filled the craft with polystyrene billets, which work fine as buoyancy. What I like about polystyrene is that it is light and cannot absorb water. My Mako Millennium has an air filled gland which is acceptable but always has the chance of being compromised due to friction, wear and tear and time.
A few years back I refurbished ski-boats and we would remove the 2 liter bottles and replace it with 2 part expandable urethane foam, it's excellent and has a negative water absorption rating... Then again, as with everything it's all about preparation, preparation, preparation.
I think, adding a little weight for the sake of safety is a fair compromise. I also think that although trying to enforce the rules I believe it's the responsibility of each boat owner to make sure his/her craft has the necessary buoyancy. Manufacturers today should actually provide you with a certificate of buoyancy.
That's my 5 cents...
