Skycaddie membership | Golf Monthly

I believe that the courses on SkyCaddie have been walked and manually calculated for the yardages whereas companies like TomTom just use satellite and GPS to map the courses. In saying that, I have a TomTom and my PP has a SkyCaddie and they are always nearly identical (maybe 2 yards out max, and thats not to say that the SkyCaddie is the correct one!)