Well, I confess to being partly guilty. I used the T-shaped one on the right to tap onto an existing 14-2 run to add an inwall receptacle behind a plasma TV.
One major difference in our uses, to me anyway, is that the junction is under the house, where it's exposed, and that the load is no more than about 2 amps.
I looked over the device carefully before deciding to use it, and consider it adequate for the job. Each conductor's connection is actually two points of contact.
The cost is about equal to two J-boxes and wirenuts ($6 range), it was easy to do hot, and took less than 10 minutes. I consider this to be safe and legal.
I say two J-boxes, because there was little slack in the tapped run, which means I would have had to use two boxes and a 2-foot piece of NM between them, and 6 joints. Edit:
By the way, there is no mention of in-wall (inaccessible) use of the device in the article.
[This message has been edited by Larry Fine (edited 01-25-2006).]