I had a pair of PM-10s bi-amping my 805D2s and D3s. I thought it was a lovely setup even though the room could have used some work.
I briefly used a single PM-10 on my 800D3s. I have read several articles and seen B&Ws in house with Marantz and the development of the reference product.
I LOVE the build quality of the Marantz reference gear. The PM-10 and SA-10 is gorgeous. the SA-10 is a TANK!
I recently have switched over to an all Mac system and the added power and "Mac Sound" have been welcomed.
While I really enjoyed the PM-10, I am not sure I am sold on class D. I have nothing negative to say about the PM-10. I put the fit and finish right up there with the best of them IMO, even surpassing Mac.
Now the SA-10. That is a special piece!
Sound wise, I am happy to be on a new journey with McIntosh even though I have no experience with the 8900. If I was considering the 8900, I don't know if I could stop there with the 803s. I would probably push/pull/drag whatever it took to get that 9000