I
painted the bottom of my boat with Signature Finish paint about 5 years ago and it's held up very well; boat has been left in water for as long as 2 weeks with no problems. Tom definitely knows his stuff and I'd have no problems going with whatever he recommends. As far as I know, Signature and the stuff Island Trader used (Insignia) are the only urethanes that will hold up below the waterline. Terry had his professionally sprayed, but Signature is very user friendly, is easily repaired and buffed out, and is well suited to a do-it-yourself application.