I searched here, there, everywhere. Not much to be found on these guys. AR does not have a legacy page, and Aria has tons of upgrade stuff, but no revies or opinions.
Having had owned (3 ARC preamps, one Counterpoint) and sold both as a dealer, in the field they are comparable reliability wise. ARC is one hell of a lot more expensive to repair. Both sound good, but I couldn't compare the sound of the SA-3.1 to the LS8, it is a newer product.
Elliott can update the SA-3.1 to a point that I would expect the LS-8 would be no competition, but it isn't free. Look into the SA-5 (with the tube power supply), or SA-3000 as well. Both are better than the SA-3.1. They seem to sell in the sub $500 range. Personally I think ARC preamps reached their sonic zenith when they built the SP-6A. I was not as big a fan of their early 6dj8's circuits, especially the sp-6c and all of its variants. They needed some time to learn how to make a circuit that complimented the 6dj8.
I have had gear from both companies, but not the particular units you are referencing. I did own the Counterpoint 3 not 3.1.
Bottom line. Unless the Counterpoint unit is a steal, and what I mean by steal is no more than 10% of retail, then I would run. Counterpoint gear is built like junk, at least the gear I owned. Did sound very nice when it was working, but that never seemed to last more than a few days before something broke. Of course if you are handy and can fix things, and like to fix things, then the Counterpoint might work.
This post is made possible by the generous support of people like you and our sponsors: