I would be more inclined to believe the 500HP story while GM still produces the engine for its consumption. Since GM is not using the engines anymore, who is producing the engines ? And why would the 500 and the 525 be any different since they are the same engine sans a few head, cam and exhaust changes ?
I do not know what is actually happening at Merc and am pissed that no one from the Merc is here to answer this.
It does however make sense that a big exec. from Merc would try and tell someone that the 525 was a much better engine.......since it is not much more than a 500HP and carries a much higher price. Not that gouging boaters would be something that Mercury would be involved in