heres my combo , i need more.....help

lead, the lunati cam is not much bigger would you see much difference there . i was thinking 513/533 hyd. cam or bigger.

rumble, will a hyd. cam w/6800 rpm rating be as good as a solid lifter cam rated at 6800 rpm's. i really dont want to spin past 6500 but i'm looking at these cams to raise my torque to a higher rpm.
i know an old school guy that use to spin his cast crank 360 past 7200rpms, but i dont want to risk more than 6500rpm's