It's like Frederick Brooks mythical man-month (if one man can write a software program in a year, then 52 can write the same one in a week). Nevertheless, that is how commercial products get tested. If you are Ford, you do not take 4 trucks and test them for 250,000 miles each to get a million miles of testing. You take a hundred trucks and run them each 10,000 miles.
In this case, if someone runs one of those tags across the country - 3000 miles - and doesn't have any issues with it, then I'd say that is a decent test. If I were buying one, my attitude would be the same as with all aftermarket equipment - it probably isn't going to be perfect, you are hoping that the flaws you are sure to find will not be terminal.