Interesting thread as I'm in the middle of the exact same problem. I have a Creek 5350SE in my system now. Over the last week or two, I was able to borrow both a Classe CAP-151 and a Plinius 9100. The order of my preference is:
Classe
Plinius
Creek
The Classe had the best detail, imaging and soundstage with the 1.3MKII's, but was not very musical (boring)
The Plinius was the most musical and engaging, but just couldn't beat the Classe's in it's strong points.
The Creek wasn't bad in all areas, but wasn't in the same league with the other two.
If I had to pick between these three, I would go with the Classe and not be totally happy. I plan to listen to the Plinius 9200, and probably buy the same. The Plinius sound is great, and from what I hear and read, I assume that it will have all the detail, imaging and soundstage that I will ever want. For $1200 more, I surely hope so.