My point is that when approaching the length limit on data cabling, you get more likely to come across transmission errors. There are testers that can tell you if a particular cable can reliably pass certain kinds of traffic. These are very expensive, and what I was referring to in a prior post. All the $4 tester does is see if the connections are terminated properly and that there are no breaks in the line. I can see the former for free, and the latter almost never happens after installation.