Pass Labs INT 60 VS. Primaluna Dialogue Premium HP VS. Arcam A49

I concur- gbmcleod

the Sasha and Sophia can handle a tubed power amp like ARC.
The way it was explained to me- if user enjoys electric guitar/electric bass-driven music, then, a robust SS power amp is the order on Wilson speakers.

^^perhaps the Pass int 250 is up to the job?
Though there are a few intergrateds that can handle 2 Ohm loads, that kind of load is typically where separates are called into duty.
^That doesn't make sense to me, perhaps an explanation is in order.

That Wilson says it's ok, doesn't mean that much to me. Speaker manufacturers often say such things so as not to lose sales and embarrass their retailers. What will work, and what will work best are different things.

Unsound, thank you for your input. I only have space for an integrated amp and want to make the right decision. The Arcam A49 powered them very well, just looking for a change and something with even greater detail. I believe the Sasha's are 4 Ohm. 

Unsound, 
That's a fair point but I don't believe that Wilson would offer that advice in a generic manner for the sake of politeness and not wanting to offend. Given that they have used tube amplifiers during presentations and there's ample feedback from Shasha owners who've happily used tube amplifiers. 

I'm left to conclude that both tube and transistor power amplifiers can and have been used successfully.  As is always the case it is depends on what type of sound character and presentation a listener seeks. I'm well aware of the speaker's test measurements yet also recognize the very good outcomes attested to from the use of an appropriate tube amplifier in numerous systems. 

This and other forums are replete with experiences of happy Shasha/tube amplifier owners (and SS amplifier owners  as well).
Charles