Intially looking for preamp I was thinking features on board dac etc, but then I figured you can't beat a separate preamp and dac from a purist stand point. I liked the Mcintosh C53 and the Classe' Delta preamp when it came to features. Then I decided I need simple but high performance and quality, basically inputs and the best volume control of the signal is what I want. I narrowed it down to a used Pass Labs X-12, Ayre KX-5emp and an Ayre KX-5 Twenty, with the latter being much more even if I could find a used one. I found one and stretched to purchase the Ayre KX-5 Twenty. It's solid, the resolution at lower volumes is phenomenal and it's very dynamic and yet flat across the spectrum. Very detailed and airy, I definetly can tell it's a quality component.
I didn't do any demo, rolled the dice when I bought it thinking mainly cost is relavent to performance. With some preamps it's the features, I was just looking for the best I could afford that controls the volume between the source and the amp. The Ayre KX-5 Twenty delivers that performance I was looking for but there's plenty others that compete. As we all know, it's how deep you pockets can go in this hobby, the more you spend the more you'll hear in the sound. I wish I could afford a Ayre KX-R Twenty preamp, but that's the price of putting a decent vehicle in the driveway..