The Ref 3 should be fine for many, many more years to come. I wouldn’t worry about it especially since you’re not too far from them if you wanted to make the trip and shipping probably not too bad. Not to discredit a quality tech, but a preamp to that caliber I would send it back to ARC regardless and not take a chance on it. Have the tubes checked if you can, and when the time comes, spend the little extra and buy new tubes from ARC or make sure it’s a trusted seller if you go elsewhere.
