I have be run for a few year and I be currently train for my third marathon . I have spend thousand of dollar on shoe , sock , supplement , shorts , rub , headphone , etc etc etc. . this be by far the very best return on investment I have get . it be simple to use , if you can use a smart phone you can figure out most of the feature without read the manual . I think base on the review it be the best combination of feature , display , quality and price available and I be right . this really be a excellent product and I can not wait to use it over and over .