I asked a Registered Piano Technician (RPT) with 30 years of experience for his take:

represents a refinement that leans closer to Kawai’s handcrafted Shigeru series. Performance & Touch The most significant upgrade in the is the increased control for the player. : The

For a classical pianist, the adjustable duplex is a godsend. For a jazz player, you might disable it for a purer fundamental. The RX-2 gives you no choice.