I would like to compare my P9 (latest model with RB1000) to the P10. When I bought the 9 I favoured it over a fair few decks that I tried, these included the gyro with tecno arm, Notts Anna Ace space with SME, Roksan with Tabriz, a LP12 of some spec at silly money. The choice for me came down to the P9 or Roksan, I am still not sure what made me go for the 9 over the Roksan, but for sure the fact that I was able to home demo the deck with Apheta and los certainly helped to swing it. I had a benz Glider to play with at the same time, the apheta become the keepr, and I sold the Glider on, and hearing what the Rega combo could do in my system/room made it a easier choice. The other decks are all just as good, and it is more a case of pick your poison rather than one being better then the other.
The gyro has probably the best soundstage, but got a little ''congested'' in heavy musical packages, the NA a very powerful and in control type presentation, that could be a little clinical, although you could call that good control, the Roksan hangs everything together really well, and The P9 just seemed to me to walk the middle path, but with a Rega style presentation, (fleet of foot?)
I dont think you can argue that one deck is better then the other, they are not. They just go about doing the job in different ways, one will suit you mare than the other. Change the arms on any of them and the results would change. If I was buying now I would want to try and hear the ace space with a AN arm, and OL Zephyr.