I’ve done a few runs with my new AW4 and I’m finding it is consistently recording higher distances than both Garmins and previous Apple Watches on the same routes. The differences are not massive — say 0.13 miles on a 6-mile route. I know one can drive oneself nuts by undue fretting about GPS accuracy. But I’m not clear whether some specific units might be more accurate than others so that I might benefit by exchanging the watch while still inside my 14-day return period. Btw, I live in an area with no general GPS reception problems in terms of buildings or trees, etc. In other respects, I like the AW4 a lot.