That price for 1872A on eBay is superb. I suspect someone must have had a few boxes left over after a job, because that's ridiculously cheap. 1872A is "Mediatwist," which means reduced skew, at some cost to crosstalk (though whenever we've made cables with it, the performance has been just great, so I don't mean to suggest that it's a large drawback). Two small caveats: (1) some people hate 1872A because it's more difficult to terminate into standard RJ-45 connectors due to its wide flat profile, and (2) many RJ-45 connectors will not easily accept 23 AWG bonded pairs, so termination could be a struggle depending on your connectors. But it's great cable as long as having to learn a slightly different assembly routine (and/or maybe needing to change what connectors you use) doesn't bother you.
Hints. Hmmm. Well, of the three seven-footers that failed not only their applicable specs but also failed 5e, one was from one of the three largest office supply chains in America; one was a venerable brand name in consumer electronics which used to be a byword for quality, now available at hardware stores among other places (I bought it at one of America's largest hardware store chains); and the third was from a well-known online-only brand. As I indicated in the article, I did not try to cheap-shop these--it would have been very easy to find failing cables by buying from poorly known outlets with questionable-looking product, and instead, for a reasonable comparison, I thought we had better buy cables that our customers are likely to have seen, from stores where they are likely to shop.
