ARC LS27 vs ModWright LS36.5 for Pass Labs XA160.5's?

As the title suggests, looking for some opinions on which way I should head. Both can be had for the same price, but the ModWright will come with a 2yr warranty as it's an ex-demo unit from a dealer. What would some of you knowledgeable folks do? Anyone happen to have experience with either of these combinations? Unfortunately I don't have the opportunity to hear them in my specific system first. 

System right now consists of:
Pass Labs XA160.5 amplifiers (will be running balanced, 30kohm input impedance)
Focal Scala Utopia speakers
As-yet-undetermined DAC
No analog front-end at the moment

On paper, the LS36.5 is better in terms of impedance matching but I've read a lot of folks have great success pairing ARC pre's with Pass Labs (the editor of Tone Publications said the Ref5SE sounded amazing with XA160.5's for instance). I would assume the ARC is a better preamp based on price and pedigree, but folks say the ModWright punches way above it's weight-class. Just looking for some opinions from the audiogon crowd! I'm leaning toward the ARC but worried about a mismatch despite reading the opposite from some users online.
I use a LS36.5 and it is a great preamp and matches very well with my Pass X250. No doubt the LS27 is a fine preamp as well. I took home an older LS25 MKII to compare to my former ModWright SWL 9.0SE and the ModWright was better to my ears in every area so I made the choice to go with the LS36.5 and have no regrets whatsoever. I will likely at some point send it back in to Dan for the DM upgrade but in no hurry. If you need multiple balance inputs then the ModWright is possibly not the best choice as it has only the one. Doubt at this level you or anyone would be disappointed with either piece. Dan would probably send you a unit if you called him to evaluate... super great guy.

Well, not exactly what you are asking but....

I've owned both MWI 36.5 and an ARC LS26, running them with both MWI and ARC amplification. Both are excellent. Between the two I favored the MWI for sound and the ARC for features and ergonomics. They are very close in sound quality and performance--I think you would be happy with either so maybe the question of system matching becomes more critical? As a related aside, I know you said you want to run balanced but if you are willing to consider a SE alternative I have found the Herron VTSP-3A (RO3) to be substantially better than either of the above. Not sure about impedance matching with the Pass gear but I'm thinking you would be fine. Just a thought...

Thanks for the thoughts guys. One thing of note with the LS36.5 is that because it's a dealer demo the price is well over the average used price that I see them sell for. It would seem that the "value" is in favor of the ARC @ 50% off its retail price before taxes. If I were to resell the LS36.5 I might stand to lose quite a bit whereas if I resold the LS27 I might not lose anything, but surely not much if I did.

Re: the comparison with the MW vs LS26, supposedly the LS27 is a big improvement and ARC claims it surpasses the Ref3 in every regard and sounds like a Ref5 "baby brother".

One thing I like about the MW is the potential to upgrade to the external PSU at a later date. 

One thing I can't seem to find out is what type of volume control implementation the ARC uses, I know the MW uses a potentiometer which a lot of folks don't seem to like but none of the reviews I've read seem to complain about it.

It's a really tough decision for me... can't make up my mind!
If you can afford the XA160.5, I would go with at least the Pass XP-20, or the XP-30.

Personally I would look at $10,000 plus list price preamps.
I would also consider the SimAudio 740P preamp as a good option with your Pass amps.   I'm using it with my Pass X250.8 and the two go together very well in my system.

I also owned the Pass XP-10 and Hegel P20 preamp with the X250.8 but the 740P was in another league (as it should be for the MSRP difference).
I was fortunate enough to find a nicely priced demo unit.

The LS36.5 was on my short-list to try, but once I tried the 740P I stopped my preamp search.   Yes, it is not a tube preamp, but the Pass amps are already a bit laid back and throw a nice sound-stage, so coupled with a highly transparent+neutral solid state preamp is not a bad choice either.

I must say I was floored when I hooked the 740P up for the first time with my Pass amp :)   The sound-stage and transparency of the two are amazing.    I had tried the no preamp option for a short while (Berkeley Alpha Dac 2 direct into the X250.8) and the resolution and transparency was excellent, but adding the 740P added much more sound-stage depth and overall 3 dimension-ality to the music.    The loss in transparency was very minimal if noticeable, more like just pushing the music further back, but the advantages were much greater.    That being said, any of the preamps listed in this thread are definitely very expensive volume controls assuming you don't need switching like in my case (single digital source)...

Good Luck.

what cabling are you using in your system?

which cabling are you guys using?
I'm using Shunyata Ztron Anaconda XLR ICs and 6 ft speaker cable.
One of the ICs is yet another extra cost for me,  for going with a preamp :(
My power cables are all various Ztron Shunyata as well.     It took me over a year to find+build the complete set of used  Anacondas ICs and speaker cables, but they are worth it!  Killer cables for the used prices they go for when they do come up for sale.

My speakers are Magico S1s so cables and preamps have no place to hide in my system...