I have noticed that the XA amps (full Class A) have a thicker and softer sound that the "X" amps. That's not to say that the X amps are thin (they are not thin sounding at all), but the XA does have a very slightly different sound. XA being more tonally rich, but in a way more colored as well. Full Class A is harder to do because of demanding power supply requirements. That's why they usually aren't high power (160 watts is an extremely high amount of Class A power).
Pass labs x260.8 versus xa160.8
I own and enjoy x260.8 but was curious whether xa160.8 would be upgrade but have noticed many listings for xa160.8 and rarely for 260.8. More people buy the xa160.8 or more happy buyers of 260.8?