Both are excellent integrated amps and there are several more out there including tubed integrated. I have not heard both of the units you asked about but perhaps the two links below will help. BTW I own a Luxman 590 AXII, among others.
Advice for Amp to Drive Klipsch Forte IVs
I just got back into hifi after being away for many many years. My first system, when I was 18-19 was a Kenwood KA-9100 amp, KT-615 tuner, Denon TT, Klipsch Heresy speakers and Teac reel to reel. Loved that setup in a small room. That was 1979-80. I’m now almost 60...LOL...and I’ve got time and money.
Just earlier this year I bought some KLIPSCH Forte IVs, a Denafrips Pontus II DAC, CXN V2 and a small Reisong tube amp while I got on the list for a set of Decware amps. I decided I couldn’t wait and have decided to go SS.
I listen to down tempo, Trip-Hop, Jazz and a little of this and that in a fairly small space. ...maybe 15x30.
I’m considering the Pass Labs INT-25 or maybe a Luxman L-550ax ii.
I do not have the opportunity to demo either of these but have read wonderful reviews and have watched some nice videos about each.
I wanted to get some thoughts on this set up. A brand new Luxman goes for about the same price as a demo INT-25.