With the 525's you get the Xr Drives vs. the standard Bravo's.
525's = 90-91 mph
496's = 80-83 mph
I think you will see better resale on the boat down the road with the 525's as well.
The 35Zr becomes a driver's boat once you hit the 90 mark. That is where the extra length of the 38+' boat starts to really show itself.