A lot of SE folks have Traqmate. The Traqmate guys are in Atlanta and race at a lot of the SE events. That's probably one reason. I don't know what features make the DL-1 more sophisticated, but I haven't used all the features of the Traqmate software. Being able to compare your laps against someone else's (preferably faster than you ) is a big deal so definitely factor that into the decision. I've been happy with my Traqmate.

David