Coincidentally I just got an email from Cary Direct about the SLI80, and in a review a customer is raving about the soundstage and the Hexfreds:
"I am currently a couple of weeks in with this great amplifier in my system. I am using it in mainly ultra-linear mode (but also like the triode option), driving Audiovector QR7se's. I have a Bluesound node acting as a streamer with a Chord Qutest DAC in the mix. Wow. This amp sings. I went with the Hexfred upgrade, but all else is based. The soundstage is incredible. The Cary team was also great with the purchase process, and the amplifier arrived less than a week after ordering. Very happy with this product."