I can't beleive this watch can do everything a Mychron 4 with GPS can do....  well almost except the Mytach doesn't log your RPM, but since everyone already has a Mychron or Alfano, then it doesn't  matter all that much.  If all you want to do is in depth analysis of your driving, including braking points, apex points, exit speeds and apex speed, this this Mytach handles it easily.  Best of all it is way cheaper than regular data systems.