Fist Watt F6 vs Pass Labs XA 25

I owned the XA25 and now the SIT3. I had these both side by side for 6 months before I decided to keep the SIT3. 
The XA25 has more drive and is quite neutral sounding..  A bit flat compared to the SIT3, but a better match if your speakers are not efficient. 

The F8 was designed to replace the J2 and is bit different sonically according to FW documentation. One of Nelsons partners, Joe Summat, who sadly passed on a few years back and was the “keen” hearing guru at Pass labs said the F8 was the best sounding amp of the FW lineup. This was 6 years ago when it was designed and recently put in production.  
I love how each FW amp is a different flavor and needs the right pairing of speakers to get the most from it..  

For those who don't know,,,,Joe Summat is Mark at Reno HiFi's father.

I asked Mark about his father,and he had some great stories.

FW > Pass 

I’d look at the Clayton Audio S40 before the XA25.  It’s double the power into both 4 and 8 Ohms over the Pass and costs $400 less, and it probably sounds even better.  Just not as much press.  My $0.02 FWIW. 

But does the Clayton slide into class A/B and then provide 80w into 8 ohms and 130 into 4?