BruceK, no can't remember what the other product was but doesn't matter as i will stick to Prop Speed , have been using it for well over 10 years now and wouldn't do it any other way.
Have used all the other systems previously, hard anti foul, AP 4 etc, etc none were successful especially if you laid up for a month or so.Being a timber boat I haul out every 12 months especially here in tropical waters , give the antifoul a quick lick and check for worms and as long as the yard people don't stuff it up Prop Speed every 2 years.
"When I die I hope my wife doesn't sell my toys for what I told her I paid for them"
Money: It's made round to go round , not flat to stack.
"Get out and do it"