The older Beemers have reserve switches. In traffic, you can just flip the lever when it starts to sputter. Mine never died in such a situation. My '10 RT, just died in the fast lane of the interstate at a very awkward place. No left shoulder, I had to coast over to the right shoulder across three lanes of traffic. And that had to be done just right, in order to weave between cars in rush hour with no power whatsoever. Talk about high drama! OK, so, once I knew the strips were unreliable, and what with no reserve switch, I used a dry-erase marker to write the mileage until the next needed gas stop that did include ample reserve. After my 3rd strip on the '10 RT, it never failed in the next 20,000 miles. My '11 RT fuel strip has been reliable thus far (10,000 miles).