I am having my bottom soda blasted this off season. I plan to barrier coat it and painting it with a top quality multi-season ablative. After disasterous results with cheaper water based paint I don't want to skimp. I hear good things about Micron Extra except it tends to build up over time. I always liked Petit paints but never used Ultima SR 40 or SR 60. Sounds like the Ultima SR 40 and Micron Extra are close with 40% and 39% copper respectively. The Ultima SR has 60% copper and seems superior to both. Bluewater Copper Pro SCX 67 has 67% copper but not sure of the quality of this paint. Any advice would be appreciated. I want to make the right choice before buying 4 gallons of paint. It will cost almost as much as the soda blast. Thanks.