Which way is better? Seems like I could do a 496 SC for less and go as fast as the 525. But if i ever whippled the 525, that'd be a fast boat.

If you have the extra $$ to go for a Merc 525 up front your boat will go 7-8mph faster and hold it's value better.
I would not Supercharge a stock 496HO; it has cast pistons that will melt from the added heat.
I would suggest powering with a 496HO. When the warranty period is up go for a 496 HO to 525HP upgrade kit from Raylor or Tyler Crockett.

Todd, if you can pull off the 525 money wise thats the way to go, best all around motor, every sportboat company uses them.

Or This A JC Performance Motor

801HP for under 30K.

Is the difference in price $!5 fromt the 496 to 525?

Sticker price ( list ) 496 HO With/XR $$ 32K......525 XR $$ 47K.......Those are list prices, no one pays that.

Or just have us build ya sumthin.

How much would that cost??

It all depends Todd. If you do a merin or dart block opposed to chevy, TBS vs. Whip AFR vs. Canfield it all depends.