Mcintosh vs. Audio Research tube preamps

Has anyone had the opportunity to compare, say, Audio Research LS25 with a Mac C22 original or commemorative? They have very similar values on the used market and I was curious as to anyone's perspective. Or say the LS25 (i or ii) and an MX110. I suppose I would expect to hear that the vintage Mac stuff is warmer with more rolled frequencies, but I'd love to get a first-hand impression from somebody. The LS25 mark 1 is also supposedly tube-euphonic, as well. It's a good topic for the old database!
I had an MX110 for a while but never had any tube ARC preamps. I rebuilt the MX110 completely and it sounded a lot more modern afterwards. Beforehand, it was soft and was lacking top end extension. Afterwards, it was surprisingly good. I wasn't expecting to hear a sort of "hifi" sound with excellent detail and transient snap - not exactly "tube-euphonic.". But I wouldn't advise you getting an MX110 (or original C22) without an overhaul - they are 40 years old these days.

the c22 commemorative is superb in every way, and the newer c220 and c2200 as well. i wouldn't describe them (or the arc's) as anything but neutral however...not like a cj or the holy grail, marantz 7.
Art -- Yeah, ravages of time to be sure. That's a good point, suggesting (to me, anyway) that a real A-to-B comparison might be the C22 Commemorative and the original LS25, i.e., not mark ii. Thanks for your input.
I had a C20 for thirty years -- has very nearly the same circuit as the C22. Also owned an ARC for a few years, but it was an LS17. I agree with Jaybo that they are both more neutral than the cj's or many other vintage pre's. To my ears, the mac was more euphonic, and easier to listen to, but probably less transparent (or maybe it was just aging).

Just another data point. Given the choice, I'd go for the Mac, but I like the Mac house sound more than I like the ARC house sound.

I'll never forget years ago hearing the ARC SP11 in a high-end store when it first came out. I don't remember the amps, but the speakers were Maggies. It sounded as if you were hearing live music through an open window, so open and transparent was the sound. There was little or no bass, but such openness and transparency I've rarely heard since. The spacial dimension was remarkable.

My gut reaction is that vintage Macs are more colorful, the ARCs more accurate. I'm interested in a blend of the two, and I suspect that the SP25 mark 1 would be a good contender. If you have any thoughts, please feel free to chime in. Thanks again for your thoughts.