Hey, why go to 530....go all the way and use 520. World Superbikes do and it is lighter, along with hardened alloy sprockets...way lighter. That is what we use on our M3 CR750 and CB750 racers. never broke one, never had a problem.
Our sponsor, Sprocket Specialists will make you any sprocket you need for rear or C/S (countershaft)
Yes, on a dyno that measures acceleration, smaller, lighter chains/sprockets will make a difference, but I don't think many riders could "feeL" it... by seat of pants.
Some guys will even have a "dyno" rear wheel at the ready... that has no rear brake (eliminates drag) smallest chain size that will not break on a few runs and special friction reducing grease in bearings, just to get "big" numbers. Not a real test, but makes some guys who like numbers, happy.
remember....HP is a number and torque breaks parts!
KOS (king of speed)