Hi, I purchased a TomTom GPS watch, model 8RS00, I love everything about it except for the precision, and unfortunately that is the most important thing. Is this common for this model GPS watch? Some workouts can vary by 0.2 to 0.3 miles per mile. It does not sound like much, but when running five miles over the same route, the distance my watch reports can vary as much as 0.15 miles for the total run which is extremely frustrating. Any advice besides buying a new watch?