[Silverback51]

Okay, let me try again to answer your question.

I had approximately 8000 miles on mine when I pulled them off. No issues regarding side walls or the tread area.

The reason they are not DOT approved is that since they have thinner cross sections, they will not hold up to the side walls being rubbed into curbs, nor will they hold up to rough railroad crossings or pot holes. As long as they are not damaged during mounting (happens more often that people know), and you do not curb them and avoid pot holes you should be fine.