We have two boats. A 28' Islander and a 15' Marshal Cat. I have been using an ablative, solvent based, copper on the Islander and an ablative, water born, copper on the cat boat for 5 years. I see no difference in the protection. The vehicle, (solvent or water) doesn't seem to affect the af properties. I prefer handling the water born paint and am planning to use it on both boats from now on. Who needs to smell xylene if you don't have to? I didn't try the water born paint as a response to any regulation. I just liked the thought of getting away from handling the solvent. Clean up is much easier and more pleasant. Water is cheaper than xylene, too.
TBT used to be my fave! It was / is very toxic. Copper allows considerable more fouling than the TBT of old. There wasn't even slime with Micron 22. Seal Harbor "enjoys" a reputation of being a high fouling harbor. Now, all I get is slime if I use the boats. The ablative properties along with the copper keep them reasonably clean. The only "beard" I get is from splash at the boot tops. Perhaps it is time to raise them? Water borne technology has come of age and we should embrace it for personal convenience and safety if it works. I think it does. It has for me.
As far as a substitute for copper, I don't have any experience with any of the new copper free af paints, yet. I guess it is time to try one. I will paint the cat boat with a water born one this year and see how it works.
Having to remove all old copper is over the top!
If it was in an ablative paint it has ablated! If it was in a leaching paint it has leached. If it is in a hard paint it is contained.