I'd be anxious to see if this is even worth worrying about. Buying used, shouldn't age, condition, model, proximity of seller etc. be much more important then if it has a THX logo on it? I see Monster selling really cheap cables badged THX and believe they're junk. But sure enough, the big box retailer's salesperson is quick to point that THX certification a reason for spending a little more on them.
Hope you don't miss a perfect Bryston amp for you worrying about this.
Hope you don't miss a perfect Bryston amp for you worrying about this.