Swapping W4S to Pass Labs XA- worth it?

The only measurement concern I have is iinput impedance (30K for Pass vs 100K for W4S), as I will drive ( driving) them directly from CD player/DAC.
But more importantly - will there be serious difference in sound quality. Did anyone ever compared them both?
I do not have "golden ears", but for example when I swap various CD players/DACs I can hear often significant differences. With amps I simply do not have enough experience.

It's a no brainer.

If they can drive your speakers, I would go with the Class A Pass Labs. I think the 0.8 series have higher input impedances.

Just checked - output impedance of my CD player/preamp is 300 Ohm, so in theory 30K input results in 100 ratio, which should be OK, I hope. 
Wonder if anyone drove Triton One with XA30.5 (30.8)?

I've successfully used an XA30.5 with 85db speakers.

I'd have trouble thinking of any Pass and any W4S product even remotely in the same league.

Not sure where this 30kR input figure is coming from, but the 30.8 is 50kR in SE. 

Beyond that, I have a difficult time suggesting someone buy a class A amp and operating it in class AB a significant portion of the time. We're talking about an amp that's making 1% distortion at 30 watts. At 40 watts that number has probably doubled. And what are we calling clipping? Because I can promise you the output devices themselves are clipping at 40 watts. I have no doubt this amp will belt out way more than it's rated power, but that's not it's intended use. That's how the X series is intended to be used. I'm more concerned than I would normally be since the OP mentioned piping HT audio though this thing. I'm not saying don't buy it or try it. I'm just pointing out the things that I think should be considered.