Preamps: Ayre K-5xeMP vs Pass Labs XP-10 vs Arcam C49

I used to own the Ayre K-5xeMP and it's still the best preamp I've ever owned. I sold it in the interest of trying something different.

With that said, has anyone compared the K-5xeMP with the Pass Labs XP-10 or the Arcam C49? I know the latter isn't perceived to be in the same class as Ayre and Pass Labs, but I'm curious to hear any impressions. It has hardly any press (no reviews that I've seen).