I owned the LS36 (no DS) used with the KWA150SE and the ARC LS26 so not exactly direct experience with either but based on what I’ve learned would encourage you to check out the Herron 360 Reference which will likely have the best attributes of both and then add superior tone and PRaT.
@gareents hey I’m running the XA30.8 with the Sabrinas as well!
Be surprised if the OP isn’t already running balance from either preamp to one amp or the other. I also have the M/W but not with the DM. Not to get into a fuse debate but I changed them out and am happy with the improvement although subtle. Many ARC Ref owners have done the same. If you haven’t tried the Daedalus DiD’s isolation devices you should as I think they’re among one of the best accessories out there. Really transformed my LS36.5 along with WyWires P.C.
I highly recommend looking into Backert Labs Rhumba Extreme 1.3 or Rhythm 1.3. They both are extremely well made preamps and highly praised among end users. you are very to get either of these for in-home auditions.
PS: I used to own LS36.5 and a pair of KWA 150SE in mono configuration.