Are the XA 60.8s the best of the Pass amps?

I started with the widely acclaimed XA 30.8, then I moved to the XA 60.8s for the benefits of separate power supplies and more power. They’re connected in balanced mode and I’m also high passing them at 100hz because they’re connected to Vandersteen Quatros. My system does not need more power. These amps will also put out around 150 watts when called for. So given an efficient enough speaker setup, how could the larger Pass amps be an improvement? With more output devices, I’d think you’d get slight smearing of the sound in comparison due to the difficulties, if not impossibilities, of precisely matching ever greater numbers of output transistors. The lower powered Pass amps either don’t run in balanced mode or are not configured as monoblocks. With regard to the XA .8 line vs .5, the consensus seems to give the .8 line the edge. John Atkinson had said that the 60.5s were the best he’d heard at the time. The .8 version is the successor. Have I heard any of these other amps in my system? No. I’m just positing a theory based on extensive commentary.
When the .8 series debuted I spoke with one of the designers about it. He mentioned that, independent of power capacity, the design of each model in the series is different enough from the others to favor one over another. He personally preferred the XA-160.8-- which I purchased. I think I recall him also placing the XA-60.8 in the sweet spot.
I prefer the .5 series.

Sweeter, warmer, more "tube Like".


The .8 series draw 50% more power from the wall, than the .5 series.
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I prefer the .5 series.

+1 IMHO, the XA30.5 was the gem, it just wasn’t enough power for my speakers.

Haven’t heard the new XA25, but I bet it’s killer...with the right speaks.