Modwright KWA150 VS Pass XA160.5

I need new SS amp for my ATC SMC40,
Now I fill at the top high still not smooth and sweet,
Like, my Acustik lab Stella Opus drive by Melody M2A3

Now I'm looking for Mod Wright KWA150 and Pass XA160.5,
Are anyone can advise me? Which one is better,
(KWA 150 ~6,000x2 and XA160.5 ~15,000)

1) Are only one KWA150 can drive my ATC?, If can I can save money a half)
2) How beeter of XA160.5 compare with old XA160?

My Sys.
Spk ATC SMC40 + Amp Mark 23.5
Pre Melody 1688 sig.
CD CEC51XZ as Transport + Anagram 24x192 DAC
Linn LP12 + ASR Mini basic

Spk Acustik lab Stella Opus + Amp Melody M2A3
* I used same Source and Pre

Regards, DL
Hi DL, take a look at my review that just was posted here on the GON on the XA60.5's for details about why the XA.5 series amps are wonderful. I did not run the experiement comparing the KWA 150 vs a XA.5 amp, in his case it was the stereo XA30.5, but a friend did and he did not like the Modright but loved the XA30.5 and bought it. He drives ML- Summit-X's.