There are things the Kuzma Reference can do that the P9 will lack, mostly in the bass department.
If you plan to upgrade the arm from the RB300 sometime later, then the potential is better with the Kuzma. If however you absolutely do not wish to spend any more, the P9 is probably a better bet with the RB1000 arm.
If you plan to upgrade the arm from the RB300 sometime later, then the potential is better with the Kuzma. If however you absolutely do not wish to spend any more, the P9 is probably a better bet with the RB1000 arm.