Hi,can someone yell me about gps watches please? What do they do exactly? How do they work? And could anyone be kind enough to recommend a basic one that doesn't cost the earth? I have just committed to joining the local running club but am running more and really love it, am hoping to get to where I can do some serious distances or maybe even races, I think knowing how far I run etc would really help me as ATM I have no idea.... I just run until I reach home again! Thanks in advance!