I have run 3 marathon and I be eye my fourth in a few month . I do not know the exact distance of my training run , so I decide to buy the Forerunner 201 . but then I notice that Garmin have another model call the foretrex 201 . the other model have WAAS enable which mean up to 3-5 time more accurate reading ! also it have other gp feature that the Forerunner lack . however , the Foretrex lack feature like calorie count and pace -lrb- minute per mile -rrb- . but I do not need a calorie counter and I can do math -lrb- go 7.5 mph be equivalent to 8:00 minute\/mile pace -rrb- . furthermore , I hike once in awhile so this would be a nice little addition to my hike . so I order the foretrex 201 and test it out . it work really well , especially in dc . I have be use it for about 2 monht now and I have yet to lose a connection . it work in cloudy weather -lrb- do that several time -rrb- and near building and near tree . it seem like people be have trouble with the forerunner 201 and it be accuracy . I do not have such inaccury with my foretrex 201 , maybe because it be WAAS enable . I use Sportsim software -lrb- free download from sportsim.com -rrb- to download the track onto my computer and it display pace , route , distance , and elevation . you can even put a map on the background and see you route in reference to a real map . this be how I check the accuracy of the device . on all of the route I have download and overlay on a map , it have be spot on -lrb- actually , it be sometimes off by a few meter , it be not perfect -rrb- ! conclusion : the foretrex 201 and Sportsim be a killer comb if you want to keep track of accurate time and distance .